interesting prime-related integer sequences

Here are some integer sequences from The On-Line Encyclopedia of Integer Sequences that can be easily expressed as a set.

p, q, r and s denote distinct primes.

one prime factor

OEIS formula OEIS description first 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

two prime factors

OEIS formula OEIS description first items
A001248 {p2} Squares of primes. 4, 9, 25, 49, 121, 169, 289, 361, 529, 841, 961, 1369, 1681, 1849, 2209, 2809
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

three prime factors

OEIS formula OEIS description first items
A030078 {p3} Cubes of primes. 8, 27, 125, 343, 1331, 2197, 4913, 6859, 12167, 24389, 29791, 50653, 68921
A054753 {p2q} Numbers which are the product of a prime and the square of a different prime (p^2 * q). 12, 18, 20, 28, 44, 45, 50, 52, 63, 68, 75, 76, 92, 98, 99, 116, 117, 124, 147
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

four prime factors

OEIS formula OEIS description first 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
A085986 {p2q2} Squares of the squarefree semiprimes (p^2*q^2). 36, 100, 196, 225, 441, 484, 676, 1089, 1156, 1225, 1444, 1521, 2116, 2601, 3025
A046386 {pqrs} Products of four distinct primes. 210, 330, 390, 462, 510, 546, 570, 690, 714, 770, 798, 858, 870, 910, 930, 966