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A319575
a(n) = (2/3)*n*(n^3 - 6*n^2 + 11*n - 3).
4
0, 2, 4, 6, 24, 90, 252, 574, 1136, 2034, 3380, 5302, 7944, 11466, 16044, 21870, 29152, 38114, 48996, 62054, 77560, 95802, 117084, 141726, 170064, 202450, 239252, 280854, 327656, 380074, 438540, 503502, 575424, 654786, 742084, 837830, 942552, 1056794, 1181116
OFFSET
0,2
FORMULA
a(n) = [x^4] JacobiTheta3(x)^n.
a(n) = A319574(n,4).
From Colin Barker, Oct 02 2018: (Start)
G.f.: 2*x*(1 + x)*(1 - 4*x + 7*x^2) / (1 - x)^5.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>4. (End)
MAPLE
a := n -> (2/3)*n*(n^3 - 6*n^2 + 11*n - 3):
seq(a(n), n=0..38);
MATHEMATICA
A319575[n_] := 2/3*n*(n^3-6*n^2+11*n-3); Array[A319575, 50, 0] (* or *)
LinearRecurrence[{5, -10, 10, -5, 1}, {0, 2, 4, 6, 24}, 50] (* Paolo Xausa, Feb 20 2024 *)
PROG
(PARI) concat(0, Vec(2*x*(1 + x)*(1 - 4*x + 7*x^2) / (1 - x)^5 + O(x^40))) \\ Colin Barker, Oct 02 2018
CROSSREFS
Cf. A000012 (m=0), A005843 (m=1), A046092 (m=2), A130809 (m=3), this sequence (m=4), A319576 (m=5), A319577 (m=6).
Column n=4 of A122141.
Cf. A319574.
Sequence in context: A226169 A343728 A261746 * A318609 A195333 A106274
KEYWORD
nonn,easy
AUTHOR
Peter Luschny, Oct 01 2018
STATUS
approved