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A157069 Number of integer sequences of length n+1 with sum zero and sum of absolute values 40. 1
2, 120, 4002, 93500, 1687002, 24836196, 309182762, 3337508646, 31830097752, 272125000774, 2109875558208, 14977318285254, 98118326104708, 597217934730774, 3397036441760412, 18148572883826236, 91470993083858322, 436643312483178036, 1981038544180652162 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

FORMULA

a(n)=T(n,20); T(n,k)=sum({i=1..n}binomial(n+1,i)*binomial(k-1,i-1)*binomial(n-i+k,k))

CROSSREFS

Cf. A103881, A156554.

Sequence in context: A073785 A102355 A206355 * A077540 A272180 A187880

Adjacent sequences:  A157066 A157067 A157068 * A157070 A157071 A157072

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 22 2009

STATUS

approved

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Last modified October 17 15:01 EDT 2019. Contains 328116 sequences. (Running on oeis4.)