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

0,2

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).

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

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 *)

Prog

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

Crossrefs

Cf. A061039, A145910, A145911, A178971, A178977, A178978, A144448.

Sequence in context: A263776 A145879 A231210 * A101895 A260670 A260665

Adjacent sequences: A178975 A178976 A178977 * A178979 A178980 A178981

Keyword

nonn,easy,less

Author

Paul Curtz, Jan 02 2011

Status

approved