interesting prime-related integer sequences

Here are some interesting prime-related integer sequences that can be easily represented as a set. I have copied them from The On-Line Encyclopedia of Integer Sequences® (OEIS®) but I have written the formulas of the sets myself.

p, q, r, s, t and u denote distinct primes.

table of contents

one prime factor (Ω(n) = 1)

OEIS set original description smallest items
A000040 {p} The prime numbers. 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97

two prime factors (Ω(n) = 2)

OEIS set original description smallest items
A001248 {p2} Squares of primes. 4, 9, 25, 49, 121, 169, 289, 361, 529, 841, 961, 1369, 1681, 1849, 2209, 2809, 3481
A006881 {pq} Squarefree semiprimes: Numbers that are the product of two distinct primes. 6, 10, 14, 15, 21, 22, 26, 33, 34, 35, 38, 39, 46, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, 85
A001358 {p2, pq} Semiprimes (or biprimes): products of two primes. 4, 6, 9, 10, 14, 15, 21, 22, 25, 26, 33, 34, 35, 38, 39, 46, 49, 51, 55, 57, 58, 62, 65, 69

three prime factors (Ω(n) = 3)

OEIS set original description smallest items
A030078 {p3} Cubes of primes. 8, 27, 125, 343, 1331, 2197, 4913, 6859, 12167, 24389, 29791, 50653, 68921, 79507
A054753 {p2q} Numbers which are the product of a prime and the square of a different prime. 12, 18, 20, 28, 44, 45, 50, 52, 63, 68, 75, 76, 92, 98, 99, 116, 117, 124, 147, 148, 153
A007304 {pqr} Sphenic numbers: products of 3 distinct primes. 30, 42, 66, 70, 78, 102, 105, 110, 114, 130, 138, 154, 165, 170, 174, 182, 186, 190, 195
A285508 {p3, p2q} Numbers with exactly three prime factors, not all distinct. 8, 12, 18, 20, 27, 28, 44, 45, 50, 52, 63, 68, 75, 76, 92, 98, 99, 116, 117, 124, 125, 147
A217856 {p2q, pqr} Numbers with three prime factors, not necessarily distinct, except cubes of primes. 12, 18, 20, 28, 30, 42, 44, 45, 50, 52, 63, 66, 68, 70, 75, 76, 78, 92, 98, 99, 102, 105
A014612 {p3, p2q, pqr} Numbers that are the product of exactly three (not necessarily distinct) primes. 8, 12, 18, 20, 27, 28, 30, 42, 44, 45, 50, 52, 63, 66, 68, 70, 75, 76, 78, 92, 98, 99, 102

four prime factors (Ω(n) = 4)

OEIS set original description smallest items
A030514 {p4} 4th powers of primes. 16, 81, 625, 2401, 14641, 28561, 83521, 130321, 279841, 707281, 923521, 1874161
A065036 {p3q} Product of the cube of a prime (A030078) and a different prime. 24, 40, 54, 56, 88, 104, 135, 136, 152, 184, 189, 232, 248, 250, 296, 297, 328, 344, 351
A085986 {p2q2} Squares of the squarefree semiprimes. 36, 100, 196, 225, 441, 484, 676, 1089, 1156, 1225, 1444, 1521, 2116, 2601, 3025
A085987 {p2qr} Product of exactly four primes, three of which are distinct. 60, 84, 90, 126, 132, 140, 150, 156, 198, 204, 220, 228, 234, 260, 276, 294, 306, 308
A046386 {pqrs} Products of four distinct primes. 210, 330, 390, 462, 510, 546, 570, 690, 714, 770, 798, 858, 870, 910, 930, 966, 1110
A014613 {p4, p3q, p2q2, p2qr, pqrs} Numbers that are products of 4 primes (these numbers are sometimes called "4-almost primes", a generalization of semiprimes). 16, 24, 36, 40, 54, 56, 60, 81, 84, 88, 90, 100, 104, 126, 132, 135, 136, 140, 150, 152

five prime factors (Ω(n) = 5)

OEIS set original description smallest items
A050997 {p5} Fifth powers of primes. 32, 243, 3125, 16807, 161051, 371293, 1419857, 2476099, 6436343, 20511149
A178739 {p4q} Product of the 4th power of a prime (A030514) and a different prime. 48, 80, 112, 162, 176, 208, 272, 304, 368, 405, 464, 496, 567, 592, 656, 688, 752, 848
A143610 {p3q2} Numbers of the form p^2*q^3, where p,q are distinct primes. 72, 108, 200, 392, 500, 675, 968, 1125, 1323, 1352, 1372, 2312, 2888, 3087, 3267
A189975 {p3qr} Numbers with prime factorization pqr^3. 120, 168, 264, 270, 280, 312, 378, 408, 440, 456, 520, 552, 594, 616, 680, 696, 702
A179643 {p2q2r} Products of exactly 2 distinct primes squares and a different prime (p^2*q^2*r). 180, 252, 300, 396, 450, 468, 588, 612, 684, 700, 828, 882, 980, 1044, 1100, 1116
A046387 {pqrst} Products of 5 distinct primes. 2310, 2730, 3570, 3990, 4290, 4830, 5610, 6006, 6090, 6270, 6510, 6630, 7410, 7590
A014614 {p5, p4q, p3q2, p3qr, p2q2r, p2qrs, pqrst} Numbers that are products of 5 primes (or 5-almost primes, a generalization of semiprimes). 32, 48, 72, 80, 108, 112, 120, 162, 168, 176, 180, 200, 208, 243, 252, 264, 270, 272

six prime factors (Ω(n) = 6)

OEIS set original description smallest items
A030516 {p6} Numbers with 7 divisors. 64, 729, 15625, 117649, 1771561, 4826809, 24137569, 47045881, 148035889
A178740 {p5q} Product of the 5th power of a prime (A050997) and a different prime. 96, 160, 224, 352, 416, 486, 544, 608, 736, 928, 992, 1184, 1215, 1312, 1376, 1504
A189988 {p4q2} Numbers with prime factorization p^2*q^4. 144, 324, 400, 784, 1936, 2025, 2500, 2704, 3969, 4624, 5625, 5776, 8464, 9604, 9801
A179644 {p4qr} Product of the 4th power of a prime and 2 different distinct primes (p^4*q*r). 240, 336, 528, 560, 624, 810, 816, 880, 912, 1040, 1104, 1134, 1232, 1360, 1392, 1456
A162142 {p3q3} Numbers that are the cube of a product of two distinct primes. 216, 1000, 2744, 3375, 9261, 10648, 17576, 35937, 39304, 42875, 54872, 59319
A163569 {p3q2r} Numbers of the form p^3*q^2*r where p, q and r are three distinct primes. 360, 504, 540, 600, 756, 792, 936, 1176, 1188, 1224, 1350, 1368, 1400, 1404, 1500
A162143 {p2q2r2} a(n) = A007304(n)^2. 900, 1764, 4356, 4900, 6084, 10404, 11025, 12100, 12996, 16900, 19044, 23716
A067885 {pqrstu} Product of 6 distinct primes. 30030, 39270, 43890, 46410, 51870, 53130, 62790, 66990, 67830, 71610, 72930
A046306 {p6, p5q, p4q2, p4qr, p3q3, p3q2r, p3qrs, p2q2r2, p2q2rs, p2qrst, pqrstu} Numbers that are divisible by exactly 6 primes with multiplicity. 64, 96, 144, 160, 216, 224, 240, 324, 336, 352, 360, 400, 416, 486, 504, 528, 540, 544