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A027785 a(n) = 6*(n+1)*binomial(n+2,12). 1
66, 936, 7098, 38220, 163800, 594048, 1893528, 5441904, 14360580, 35271600, 81477396, 178474296, 373173528, 748843200, 1448655000, 2711882160, 4928324310, 8718517080, 15049821150, 25401694500, 41997468240, 68124925440, 108574099920, 170228167200, 262852317000 (list; graph; refs; listen; history; text; internal format)
OFFSET

10,1

LINKS

T. D. Noe, Table of n, a(n) for n = 10..1000

FORMULA

Number of 15-subsequences of [ 1, n ] with just 2 contiguous pairs; g.f. 6*(11+2*x)*x^10/(1-x)^14.

a(n) = C(n+1, 11)*C(n+2, 2). - Zerinvary Lajos, May 13 2005, corrected by R. J. Mathar, Mar 15 2016

MATHEMATICA

Table[6(n+1)Binomial[n+2, 12], {n, 10, 60}] (* Harvey P. Dale, Jan 03 2018 *)

PROG

(MAGMA) [6*(n+1)*Binomial(n+2, 12) : n in [10..50]]; // Wesley Ivan Hurt, Apr 20 2021

CROSSREFS

Sequence in context: A304838 A337896 A056468 * A271757 A228996 A196789

Adjacent sequences:  A027782 A027783 A027784 * A027786 A027787 A027788

KEYWORD

nonn,easy

AUTHOR

thi ngoc dinh (via R. K. Guy)

STATUS

approved

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Last modified June 15 08:52 EDT 2021. Contains 345048 sequences. (Running on oeis4.)