A144453 a(n) = A061039(8*n+5).

16, 160, 16, 832, 1360, 224, 2800, 3712, 176, 5920, 7216, 320, 10192, 11872, 1520, 15616, 17680, 736, 22192, 24640, 336, 29920, 32752, 3968, 38800, 42016, 560, 48832, 52432, 2080, 60016, 64000, 7568, 72352, 76720, 3008, 85840, 90592, 3536, 100480, 105616

Offset: 0

Author

Paul Curtz, Oct 07 2008

Keywords

• nonn
• easy

Comments

Numerators of 16*(n+1)*(4*n+1)/(9*(8*n+5)^2), so all numbers are multiples of 16 because the denominator is always odd.

Interpreted modulo 9, all numbers from 1 to 8 appear: a(20) is the first entry = 3 (mod 9), a(26) is the first entry = 2 (mod 9), a(80) is the first entry = 6 (mod 9).

Links

• Colin Barker, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).

Crossrefs

Cf. A020806, A141425, A146537.

Programs

Mathematica

Numerator[1/9 - 1/(8*Range[0,100] +5)^2] (* G. C. Greubel, Mar 07 2022 *)

Sage

[numerator(1/9 - 1/(8*n+5)^2) for n in (0..100)] # G. C. Greubel, Mar 07 2022

Formula

a(n) = A061039(8*n+5).

a(n) = 3*a(n-27) - 3*a(n-54) + a(n-81) for n>83. - Colin Barker, Oct 10 2016

Extensions

Edited and extended by R. J. Mathar, Oct 24 2008