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A367509
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a(n) = Sum_{d|n} (2*d+1)^n.
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3
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3, 34, 370, 7267, 161294, 4960812, 170861562, 7019201348, 322728071069, 16705828227476, 952809758091074, 59628239376008854, 4052555153020570590, 297587425607933152700, 23465266173840431204452, 1978033864507607364591749, 177482997121587371955312038
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} 2^k * binomial(n,k) * sigma_k(n).
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PROG
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(PARI) a(n) = sumdiv(n, d, (2*d+1)^n);
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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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