A178978 a(n) = A144448(n+1)/8.

0, 2, 5, 1, 14, 20, 1, 35, 44, 2, 65, 77, 10, 104, 119, 5, 152, 170, 7, 209, 230, 28, 275, 299, 4, 350, 377, 5, 434, 464, 55, 527, 560, 22, 629, 665, 26, 740, 779, 91, 860, 902, 35, 989, 1034, 40, 1127, 1175, 136, 1274, 1325, 17

Offset: 0

Author

Paul Curtz, Jan 02 2011

Keywords

• nonn
• easy
• less

Comments

Differs from A178971 for indices n > 23.

Links

• G. C. Greubel, Table of n, a(n) for n = 0..5000
• 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. A061039, A145910, A145911, A178971, A178977, A178978, A144448.

Programs

Maple

A061039 := proc(n) numer(1/9-1/n^2) ; end proc:
A144448 := proc(n) A061039(1+2*n) ; end proc:
A178978 := proc(n) A144448(n+1)/8 ; end proc:
seq(A178978(n),n=0..80) ; # R. J. Mathar, Jan 06 2011

Mathematica

Table[Numerator[1/9 -1/(2*n+3)^2]/8, {n, 0, 75}] (* G. C. Greubel, Mar 06 2022 *)

Sage

[numerator(1/9 -1/(2*n+3)^2)/8 for n in (0..75)] # G. C. Greubel, Mar 06 2022

Formula

Trisections:

a(3*n) = A145911(n);

a(3*n+1) = A145910(n);

a(3*n+2) = A178977(n).

a(n) = 3*a(n-27) - 3*a(n-54) + a(n-81). - G. C. Greubel, Mar 06 2022