A061318 Column 3 of A061314.

0, 4, 40, 304, 1720, 7480, 26404, 79240, 209304, 499140, 1095160, 2242504, 4332640, 7966504, 14036260, 23829040, 39156304, 62512740, 97268904, 147902080, 220270120, 321933304, 462529540, 654208504, 912130600, 1255036900, 1705896504, 2292638040, 3048972304, 4015313320

Offset: 0

Author

Henry Bottomley, Apr 24 2001

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (9,-36,84,-126,126,-84,36,-9,1)

Crossrefs

Cf. A006007, A061314, A061316, A061319.

Programs

Mathematica

CoefficientList[Series[-4x (1+x+22x^2+22x^3+22x^4+x^5+x^6)/(x-1)^9,{x,0,30}],x] (* or *) LinearRecurrence[{9,-36,84,-126,126,-84,36,-9,1},{0,4,40,304,1720,7480,26404,79240,209304},30] (* Harvey P. Dale, Jul 04 2023 *)

Formula

a(n) = A061316(n) + A006007(n)^2 = 4*A061319(n).

G.f. -4*x*(1+x+22*x^2+22*x^3+22*x^4+x^5+x^6)/(x-1)^9. - R. J. Mathar, Aug 11 2012

Extensions

a(25)-a(29) from Stefano Spezia, Aug 31 2023