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A160741
Numerator of P_6(2n), the Legendre polynomial of order 6 at 2n.
5
-5, 10159, 867211, 10373071, 59271739, 227860495, 683245579, 1727242351, 3854919931, 7823790319, 14733641995, 26117017999, 44040338491, 71215667791, 111123125899, 168143944495, 247704167419, 356428995631, 502307776651, 694869638479, 945369767995
OFFSET
0,1
FORMULA
From Colin Barker, Jul 23 2019: (Start)
G.f.: -(5 - 10194*x - 795993*x^2 - 4516108*x^3 - 4515933*x^4 - 796098*x^5 - 10159*x^6) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>6.
a(n) = -5 + 420*n^2 - 5040*n^4 + 14784*n^6.
(End)
MAPLE
A160741 := proc(n)
orthopoly[P](6, 2*n) ;
numer(%) ;
end proc: # R. J. Mathar, Oct 24 2011
MATHEMATICA
Table[Numerator[LegendreP[6, 2n]], {n, 0, 40}]
PROG
(PARI) a(n)=numerator(pollegendre(6, n+n)) \\ Charles R Greathouse IV, Oct 24 2011
(PARI) Vec(-(5 - 10194*x - 795993*x^2 - 4516108*x^3 - 4515933*x^4 - 796098*x^5 - 10159*x^6) / (1 - x)^7 + O(x^30)) \\ Colin Barker, Jul 23 2019
CROSSREFS
Sequence in context: A109514 A022918 A212617 * A101846 A292742 A376103
KEYWORD
sign,frac,easy
AUTHOR
N. J. A. Sloane, Nov 17 2009
STATUS
approved