A260334 a(n) = (36*n^6 - 60*n^5 + 30*n^4 + 4*n^3 + 8*n^2 - 4*n + 1 - (-1)^n)/8.

0, 2, 115, 1783, 11758, 49304, 156633, 412589, 949564, 1973662, 3788095, 6819827, 11649450, 19044308, 29994853, 45754249, 67881208, 98286074, 139280139, 193628207, 264604390, 356051152, 472441585, 618944933, 801495348, 1026863894, 1302733783, 1637778859, 2041745314, 2525536652

Offset: 0

Author

N. J. A. Sloane, Jul 27 2015

Keywords

• nonn
• easy

Links

• Colin Barker, Table of n, a(n) for n = 0..1000
• B. T. Bennett and R. B. Potts, Arrays and brooks, J. Austral. Math. Soc., 7 (1967), 23-31. [Annotated scanned copy] See b_{n,3}.
• Index entries for linear recurrences with constant coefficients, signature (6,-14,14,0,-14,14,-6,1).

Crossrefs

Conjectured to be the 4th diagonal of A260333.

Programs

Mathematica

Table[(36n^6-60n^5+30n^4+4n^3+8n^2-4n+1-(-1)^n)/8,{n,0,30}] (* or *) LinearRecurrence[{6,-14,14,0,-14,14,-6,1},{0,2,115,1783,11758,49304,156633,412589},30] (* Harvey P. Dale, Apr 14 2020 *)

PARI

concat(0, Vec(-x*(17*x^6 +487*x^5 +2108*x^4 +2642*x^3 +1121*x^2 +103*x +2) / ((x -1)^7*(x +1)) + O(x^100))) \\ Colin Barker, Jul 29 2015

Formula

G.f.: -x*(17*x^6+487*x^5+2108*x^4+2642*x^3+1121*x^2+103*x+2) / ((x-1)^7*(x+1)). - Colin Barker, Jul 29 2015