A297123 a(n) = 462*n^6 + 330*n^4 - 165*n^3 + 55*n^2 - 11*n + 1.

1, 672, 33727, 359536, 1967109, 7405696, 21949027, 55092192, 122381161, 247574944, 465140391, 823079632, 1386090157, 2239057536, 3490880779, 5278630336, 7772038737, 11178323872, 15747344911, 21777090864, 29619501781, 39686622592, 52457089587

Offset

0,2

Links

Seiichi Manyama, Table of n, a(n) for n = 0..10000

Olivier Rozier, Ramanujan's tau function

Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).

Formula

From Colin Barker, Dec 26 2017: (Start)

G.f.: (1 + 665*x + 29044*x^2 + 137524*x^3 + 135139*x^4 + 29243*x^5 + 1024*x^6) / (1 - x)^7.

a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>6.

(End)

Prog

(PARI) {a(n) = 462*n^6+330*n^4-165*n^3+55*n^2-11*n+1}
(PARI) Vec((1 + 665*x + 29044*x^2 + 137524*x^3 + 135139*x^4 + 29243*x^5 + 1024*x^6) / (1 - x)^7 + O(x^40)) \\ Colin Barker, Dec 26 2017

Crossrefs

Cf. A000594, A297127.

Sequence in context: A331666 A245782 A047728 * A335254 A160209 A234117

Adjacent sequences: A297120 A297121 A297122 * A297124 A297125 A297126

Keyword

nonn,easy

Author

Seiichi Manyama, Dec 26 2017

Status

approved