A247678 Odd composite numbers congruent to 4 modulo 9.

49, 85, 121, 175, 247, 265, 301, 319, 355, 391, 427, 445, 481, 517, 535, 553, 589, 625, 679, 697, 715, 805, 841, 895, 913, 931, 949, 985, 1003, 1057, 1075, 1111, 1147, 1165, 1183, 1219, 1255, 1273, 1309, 1345, 1363, 1417, 1435, 1507, 1525, 1561, 1615, 1633

Offset: 1

Author

Odimar Fabeny, Sep 22 2014

Keywords

• nonn
• easy

Links

• Odimar Fabeny, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A017209 (9n + 4, supersequence of this sequence), A247676, A247679, A247681, A247682, A247683.

Programs

Mathematica

Select[18Range[125] + 13, Not[PrimeQ[#]] &] (* Alonso del Arte, Sep 24 2014 *)
Select[Range[13,1700,18],CompositeQ] (* Harvey P. Dale, Aug 21 2024 *)

PARI

lista(nn) = {forcomposite(n=1, nn, if ((n % 2) && ((n % 9) == 4), print1(n, ", ")); ); } \\ Michel Marcus, Sep 22 2014