A302038 Semiludic numbers or "Ludic semiprimes": numbers n for which A302037(n) = 2.

4, 6, 9, 10, 14, 15, 19, 22, 26, 27, 31, 34, 35, 39, 46, 50, 55, 58, 59, 63, 65, 73, 74, 75, 82, 86, 94, 95, 99, 101, 103, 106, 113, 122, 133, 134, 135, 142, 145, 147, 154, 155, 163, 166, 167, 171, 178, 182, 185, 187, 194, 203, 205, 214, 219, 230, 238, 242, 243, 245, 253, 254, 255, 262, 263, 269, 271, 279, 286, 293, 298, 299, 311

Offset: 1

Author

Antti Karttunen, Apr 01 2018

Keywords

• nonn

Comments

An analog for A001358 based on the Ludic factorization (see A302032).

Links

• Antti Karttunen, Table of n, a(n) for n = 1..3953
• Index entries for sequences generated by sieves

Crossrefs

Cf. A003309, A255127, A302032, A302037.

Cf. A254100 (a subsequence).

Cf. also A001358, A302036.

Programs

PARI

k=0; for(n=1,512,if(2==A302037(n),k++;print1(n,","))); \\ Other code as in A302037.