A047489 Numbers that are congruent to {1, 2, 3, 5, 7} mod 8.

1, 2, 3, 5, 7, 9, 10, 11, 13, 15, 17, 18, 19, 21, 23, 25, 26, 27, 29, 31, 33, 34, 35, 37, 39, 41, 42, 43, 45, 47, 49, 50, 51, 53, 55, 57, 58, 59, 61, 63, 65, 66, 67, 69, 71, 73, 74, 75, 77, 79, 81, 82, 83, 85, 87, 89

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Comments

Numbers n such that A002817(n) is divisible by n. [Bruno Berselli, Dec 11 2013]

Links

• Bruno Berselli, Table of n, a(n) for n = 1..1000
• Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,1,-1).

Crossrefs

Cf. A002817.

Formula

G.f.: x*(x+1)*(x^4+x^3+x^2+1)/((x-1)^2*(x^4+x^3+x^2+x+1)). [Colin Barker, Jun 22 2012]