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A055454
a(n) = A055450(n, n-4).
6
1, 5, 14, 28, 42, 174, 735, 3155, 13726, 60398, 268361, 1202425, 5427110, 24652698, 112622124, 517102008, 2385026330, 11045344150, 51341255630, 239447037890, 1120163788030, 5254987411850, 24716226207075
OFFSET
4,2
LINKS
FORMULA
a(n) = A055450(n, n-4).
a(n) = 42*Hypergeometric2F1([8-n, 11/2], [7], -4) for n >= 8. - G. C. Greubel, Jan 30 2024
MATHEMATICA
Join[{1, 5, 14, 28}, Table[42*Hypergeometric2F1[8-n, 11/2, 7, -4], {n, 8, 40}]] (* G. C. Greubel, Jan 30 2024 *)
PROG
(Magma) [1, 5, 14, 28] cat [Floor(42*HypergeometricSeries2F1(8-n, 11/2, 7, -4)): n in [8..40]]; // G. C. Greubel, Jan 30 2024
(SageMath)
def A055454(n): return (1, 5, 14, 28)[n-4] if n<8 else 42*hypergeometric([8-n, 11/2], [7], -4).simplify()
[A055454(n) for n in range(4, 41)] # G. C. Greubel, Jan 30 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 18 2000
STATUS
approved