A275910 Numbers not congruent to 0, 1 or 8 mod 9.

2, 3, 4, 5, 6, 7, 11, 12, 13, 14, 15, 16, 20, 21, 22, 23, 24, 25, 29, 30, 31, 32, 33, 34, 38, 39, 40, 41, 42, 43, 47, 48, 49, 50, 51, 52, 56, 57, 58, 59, 60, 61, 65, 66, 67, 68, 69, 70, 74, 75, 76, 77, 78, 79, 83, 84, 85, 86, 87, 88, 92, 93, 94, 95, 96, 97, 101, 102, 103, 104, 105, 106, 110, 111

Offset: 1

Author

N. J. A. Sloane, Aug 26 2016

Keywords

• nonn
• easy

References

• H. I. Okagbue, M. O. Adamu, S. A. Bishop and A. A. Opanuga, Properties of Sequences Generated by Summing the Digits of Cubed Positive Integers, Indian Journal Of Natural Sciences, Vol. 6 / Issue 32 / October 2015.

Links

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

Crossrefs

Complement of A054966.

Programs

Mathematica

DeleteCases[Range[120],?(MemberQ[{0,1,8},Mod[#,9]]&)] (* _Harvey P. Dale, Oct 08 2017 *)

PARI

Vec(x*(2+x+x^2+x^3+x^4+x^5+2*x^6)/((1-x)^2*(1+x)*(1-x+x^2)*(1+x+x^2)) + O(x^100)) \\ Colin Barker, Aug 26 2016

Formula

From Colin Barker, Aug 26 2016: (Start)

a(n) = a(n-1)+a(n-6)-a(n-7) for n>7.

G.f.: x*(2+x+x^2+x^3+x^4+x^5+2*x^6) / ((1-x)^2*(1+x)*(1-x+x^2)*(1+x+x^2)). (End)