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A264889
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Partial sums of hyperfactorials (A002109).
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1
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1, 2, 6, 114, 27762, 86427762, 4031164827762, 3319770429936027762, 55696441261496986915227762, 21577941278638297470665013744027762, 215779412250996503370318565758665013744027762, 61564384586850833363801728392684283449726665013744027762
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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} (k!)^k/Barnes G-Function(k + 1).
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EXAMPLE
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a(0) = 1;
a(1) = 1 + 1^1 = 2;
a(2) = 1 + 1^1 + 1^1*2^2 = 6;
a(3) = 1 + 1^1 + 1^1*2^2 + 1^1*2^2*3^3 = 114;
a(4) = 1 + 1^1 + 1^1*2^2 + 1^1*2^2*3^3 + 1^1*2^2*3^3*4^4 = 27762, etc.
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MATHEMATICA
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Table[Sum[Hyperfactorial[k], {k, 0, n}], {n, 0, 11}]
Accumulate[Hyperfactorial[Range[0, 15]]] (* Harvey P. Dale, Sep 22 2021 *)
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PROG
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(PARI) a(n) = sum(k=0, n, prod(j=2, k, j^j)); \\ Altug Alkan, Nov 27 2015
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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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