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A109844 a(1) = 1, a(2) = 2, next terms up to a(2n-1) are obtained by multiplying previous terms a(n-1) by n+1, a(n-2) by n+2 etc. a(2) by (2n-2) and a(1) by 2n-1. On similar lines a(2n) = 2n*a(2n-2), a(2n+1) = (2n+1)*a(2n-1) and so on. 0
1, 2, 3, 8, 5, 48, 21, 16, 9, 160, 231, 576, 65, 112, 45, 32, 17, 576, 855, 2240, 1365, 12672, 5313, 3840, 225, 416, 567, 1344, 145, 240, 93, 64, 33, 2176, 3255, 8640, 5365, 51072, 22113, 16640, 9225, 161280, 228459, 557568, 61425, 103040, 40185, 27648 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Might be called a self-dependent or bootstrap sequences. a(n) is a multiple of n by definition. Subsidiary sequences: (i) next n-1 numbers are n times the previous n-1 terms and many more such sequences by variations in coefficients. (ii) a(n) = A(109844(n))/n.

LINKS

Table of n, a(n) for n=1..48.

EXAMPLE

a(9) = 9 a(10)= 10*a(8) = 10*16 = 160., a(11)= 11*21 = 189.

CROSSREFS

Sequence in context: A324502 A170826 A162537 * A128779 A112283 A136182

Adjacent sequences:  A109841 A109842 A109843 * A109845 A109846 A109847

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Jul 06 2005

EXTENSIONS

More terms from Joshua Zucker, May 04 2006

STATUS

approved

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Last modified July 29 12:56 EDT 2021. Contains 346346 sequences. (Running on oeis4.)