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A328685
Row sums of A309038.
1
0, 4, 28, 120, 320, 716, 1380, 2464, 3984, 6196, 9124, 13128, 18048, 24476, 32244, 42096, 53440, 67460, 83604, 103192, 124944, 150892, 179908, 214080, 251184, 294356, 341700, 396264, 454624, 521276, 593364, 675088, 761568, 858916, 963124, 1079736, 1202160, 1338380
OFFSET
0,2
COMMENTS
All the terms are even.
LINKS
FORMULA
Conjectures from Colin Barker, Oct 25 2019: (Start)
G.f.: 4*x*(1 + 5*x + 17*x^2 + 27*x^3 + 46*x^4 + 52*x^5 + 54*x^6 + 28*x^7 + 29*x^8 - 7*x^9+ 5*x^10 - 17*x^11 + 4*x^12 - 6*x^13 + 12*x^14 - 14*x^15 + 8*x^16 - 4*x^17) / ((1 - x)^5*(1 + x)^3*(1 + x^2)^3).
a(n) = 2*a(n-1) - a(n-2) + 3*a(n-4) - 6*a(n-5) + 3*a(n-6) - 3*a(n-8) + 6*a(n-9) - 3*a(n-10) + a(n-12) - 2*a(n-13) + a(n-14) for n > 18.
(End)
a(n) ~ 5*n^4/8. - Conjectured by Stefano Spezia, Sep 08 2021
MATHEMATICA
(* The function T is defined in A309038. *)
Flatten[Table[Sum[T[n, k], {k, 0, n^2}], {n, 0, 37}]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Stefano Spezia, Oct 25 2019
STATUS
approved