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A092974 Smarandacheials for k=9. 6
1, 2, 3, 4, -20, -18, -14, -8, -81, -80, -154, -216, -260, 3640, 3240, 2464, 1360, 26244, 25840, 49280, 68040, 80080, -1841840, -1632960, -1232000, -671840, -19131876, -18811520, -35728000, -48988800, -57097040, 1827105280, 1616630400, 1214752000, 658403200, 24794911296 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

REFERENCES

F. Smarandache, Back and Forth Factorials, Arizona State Univ., Special Collections, 1972.

FORMULA

a(n, k) = !n!_k = Prod_{i=0, 1, 2, .., floor(2n/k)}_{0<|n-i*k|<=n} (n-i*k) = n(n-k)(n-2k)(n-3k)... . k=9.

PROG

(PARI) a(n, k)=prod(j=0, (2*n)\k, if(n-k*j==0, 1, n-k*j))

CROSSREFS

Cf. A092396, A092397, A092398, A092399, A092971, A092972, A092973.

Sequence in context: A012285 A012281 A098503 * A058186 A024632 A012578

Adjacent sequences:  A092971 A092972 A092973 * A092975 A092976 A092977

KEYWORD

sign

AUTHOR

Paul D. Hanna, M.L. Perez and Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 27 2004

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Last modified February 16 23:43 EST 2012. Contains 205978 sequences.