A025580 - OEIS

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A025580

a(n) = (1/1 - 1/(n-1) + ... + d/binomial(n-[ n/2 ],[ n/2 ]))*L, where L = LCM{1, n-1, ..., binomial(n-[ n/2 ],[ n/2 ])}, d = (-1)^n.

1, 0, 1, 5, 13, -1, 41, 383, 901, -47, 1945, 26141, 29368, -6359, 296509, 345525, 756291, -197211, 10483329, 225371001, 242537898, -3394965, 204481239, 5215763433

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,4

LINKS

Table of n, a(n) for n=0..23.

CROSSREFS

Sequence in context: A116058 A231692 A245776 * A073878 A164793 A065934

Adjacent sequences: A025577 A025578 A025579 * A025581 A025582 A025583

KEYWORD

sign

AUTHOR

Clark Kimberling

STATUS

approved