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A168562
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Sum of squares of Eulerian numbers in row n of triangle A008292 with a(0)=1.
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4
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1, 1, 2, 18, 244, 5710, 188908, 8702820, 524888040, 40393084950, 3853034107900, 446671026849916, 61824801560228056, 10072685383683311116, 1907978676359896992824, 415795605119514578204616, 103294156408291202467520976, 29018125910193347265466916070
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OFFSET
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0,3
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COMMENTS
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Row sums of Eulerian triangle A008292 yield the factorials.
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} [ Sum_{j=0..k} (-1)^j*(k-j)^n*C(n+1, j) ]^2.
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EXAMPLE
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a(1) = 1 = 1;
a(2) = 1 + 1 = 2;
a(3) = 1 + 4^2 + 1 = 18;
a(4) = 1 + 11^2 + 11^2 + 1 = 244;
a(5) = 1 + 26^2 + 66^2 + 26^2 + 1 = 5710;
a(6) = 1 + 57^2 + 302^2 + 302^2 + 57^2 + 1 = 188908.
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MAPLE
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a:= n-> add(combinat[eulerian1](n, k)^2, k=0..n):
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PROG
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(PARI) {a(n)=sum(k=0, n, sum(j=0, k, (-1)^j*(k-j)^n*binomial(n+1, j))^2)}
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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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