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A157058 Number of integer sequences of length n+1 with sum zero and sum of absolute values 18. 1
2, 54, 812, 8580, 70310, 472626, 2703512, 13507416, 60110030, 241925530, 891454124, 3037849828, 9654482474, 28818500830, 81289041680, 217815522736, 556959705302, 1364497268946, 3214138597460, 7302195414780, 16045139112002, 34183012888134, 70764981877592 (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,9); T(n,k)=sum({i=1..n}binomial(n+1,i)*binomial(k-1,i-1)*binomial(n-i+k,k))

G.f.: -2*x*(x^16 +8*x^15 +64*x^14 +224*x^13 +784*x^12 +1568*x^11 +3136*x^10 +3920*x^9 +4900*x^8 +3920*x^7 +3136*x^6 +1568*x^5 +784*x^4 +224*x^3 +64*x^2 +8*x +1) / (x -1)^19. [Colin Barker, Jan 25 2013]

CROSSREFS

Cf. A103881, A156554.

Sequence in context: A202739 A055024 A057411 * A305693 A071798 A123686

Adjacent sequences:  A157055 A157056 A157057 * A157059 A157060 A157061

KEYWORD

nonn,easy

AUTHOR

R. H. Hardin Feb 22 2009

STATUS

approved

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Last modified April 1 10:33 EDT 2020. Contains 333159 sequences. (Running on oeis4.)