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A104968
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Absolute row sums of triangle A104967.
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4
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1, 2, 4, 6, 6, 12, 22, 32, 34, 52, 100, 150, 170, 266, 438, 640, 766, 1196, 1996, 2888, 3210, 4994, 8534, 12392, 15106, 22154, 34366, 52134, 62148, 96956, 156396, 217416, 262062, 394164, 643908, 950944, 1150368, 1689176, 2600992, 3767888, 4840338
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} abs(A104967(n,k)).
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MATHEMATICA
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A104967[n_, k_]:= A104967[n, k]= Sum[(-2)^j*Binomial[k+1, j]*Binomial[n-j, k], {j, 0, n-k}];
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PROG
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(PARI) {a(n)=local(X=x+x*O(x^n)); sum(k=0, n, abs(polcoeff(polcoeff((1-2*X)/(1-X-X*y*(1-2*X)), n, x), k, y)))}
(Sage)
@cached_function
def A104967(n, k): return sum( (-2)^j*binomial(k+1, j)*binomial(n-j, k) for j in (0..n-k))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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