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A331434
Column 2 of triangle in A331431.
2
30, -180, 630, -1680, 3780, -7560, 13860, -23760, 38610, -60060, 90090, -131040, 185640, -257040, 348840, -465120, 610470, -790020, 1009470, -1275120, 1593900, -1973400, 2421900, -2948400, 3562650, -4275180, 5097330, -6041280, 7120080, -8347680, 9738960
OFFSET
0,1
COMMENTS
Apart from the signs, essentially the same as A054559. - Georg Fischer, Jan 18 2020
FORMULA
G.f.: 30/(1+x)^6. - Georg Fischer, Jan 18 2020
From G. C. Greubel, Mar 22 2022: (Start)
a(n) = 30*(-1)^n*binomial(n+5, 5).
a(n) = 30*(-1)^n*A000389(n+5).
E.g.f.: (1/4)*(120 - 600*x + 600*x^2 - 200*x^3 + 25*x^4 - x^5)*exp(-x). (End)
MATHEMATICA
CoefficientList[Series[30/(1+x)^6, {x, 0, 30}], x] (* Georg Fischer, Jan 18 2020 *)
PROG
(Magma) [30*(-1)^n*Binomial(n+5, 5): n in [0..50]]; // G. C. Greubel, Mar 22 2022
(Sage) [30*(-1)^n*binomial(n+5, 5) for n in (0..50)] # G. C. Greubel, Mar 22 2022
CROSSREFS
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Jan 17 2020
EXTENSIONS
a(0) changed to 30, and more terms from Georg Fischer, Jan 18 2020
STATUS
approved