A343110 Numbers having no divisor of the form 8*k + 7.

1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 16, 17, 18, 19, 20, 22, 24, 25, 26, 27, 29, 32, 33, 34, 36, 37, 38, 40, 41, 43, 44, 48, 50, 51, 52, 53, 54, 57, 58, 59, 61, 64, 65, 66, 67, 68, 72, 73, 74, 76, 80, 81, 82, 83, 85, 86, 88, 89, 96, 97, 99, 100, 101, 102

Offset: 1

Author

Jianing Song, Apr 05 2021

Keywords

• nonn
• easy

Comments

Numbers not divisible by at least one of 7, 15, 23, ...

Examples

			9 is a term since it has no divisor congruent to 7 modulo 8.
		

Links

• Jianing Song, Table of n, a(n) for n = 1..10000

Crossrefs

Numbers having m divisors of the form 8*k + i: A343107 (m=1, i=1), A343108 (m=0, i=3), A343109 (m=0, i=5), this sequence (m=0, i=7), A343111 (m=2, i=1), A343112 (m=1, i=3), A343113 (m=1, i=5), A141164 (m=1, i=7).

Indices of 0 in A188172.

Programs

PARI

res(n,a,b) = sumdiv(n, d, (d%a) == b)
isA343110(n) = (res(n,8,7) == 0)