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A065805
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a(n) = Sum_{j=0..n} sigma(j,n).
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3
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2, 10, 44, 377, 3912, 57214, 960808, 19261862, 435877584, 11123320200, 313842837684, 9729290348250, 328114698808288, 11967567841654610, 469172063576559648, 19676848703371278527, 878942778254232811956
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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n=6; a(6) = 4 + 12 + 50 + 252 + 1394 + 8052 + 47450 = 57214.
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MATHEMATICA
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a[ n ]=Table[ Apply[ Plus, Table[ DivisorSigma[ w, n ], {w, 0, n} ] ].
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PROG
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(PARI) { for (n=1, 100, a=sum(j=0, n, sigma(n, j)); write("b065805.txt", n, " ", a) ) } \\ Harry J. Smith, Oct 31 2009
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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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