A179370 Positive integers of the form (7*m^2+1)/11.

16, 23, 163, 184, 464, 499, 919, 968, 1528, 1591, 2291, 2368, 3208, 3299, 4279, 4384, 5504, 5623, 6883, 7016, 8416, 8563, 10103, 10264, 11944, 12119, 13939, 14128, 16088, 16291, 18391, 18608, 20848, 21079, 23459, 23704, 26224, 26483

Offset: 1

Author

Bruno Berselli, Jul 12 2010

Keywords

• nonn
• easy

Comments

Here m=(11*(2*n-1)-9*(-1)^n)/4 for n>0.

Links

• B. Berselli, Table of n, a(n) for n = 1..10000.
• Index entries for linear recurrences with constant coefficients, signature (1,2,-2,-1,1).

Crossrefs

Cf. A113338, A179088, A179337, A179338, A179339.

Formula

a(n) = (154*n*(n-1)-63*(2*n-1)*(-1)^n+65)/8.

G.f.: x*(16+7*x+108*x^2+7*x^3+16*x^4)/((1+x)^2*(1-x)^3).

a(n) = a(-n+1) = a(n-1)+2*a(n-2)-2*a(n-3)-a(n-4)+a(n-5).