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A131972
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Sum of all n-digit Apery numbers.
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0
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2, 24, 180, 7420, 33264, 991848, 3938220, 103832872, 389398464, 9620555000, 34901442000, 828288777420, 2940343837200, 67898251759800, 237371722628040, 5373868753340880, 97581248745060600, 335240928272918304, 7415892272293658608, 25286571126114014640, 553714770886681187168
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OFFSET
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1,1
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LINKS
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EXAMPLE
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Sum of all 1-digit Apery numbers is 0 + 2 = 2.
Sum of all 2-digit Apery numbers is 24
Sum of all 3-digit Apery numbers is 180.
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MATHEMATICA
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digNum[n_] := Length @ IntegerDigits[n]; apery[n_] := n^2 * Binomial[2n, n]; digCount = 0; sum = 0; cumsum = {}; Do[a = apery[n]; If[digNum[a] > digCount, digCount++; AppendTo[cumsum, sum]]; sum += a, {n, 0, 35}]; Differences[cumsum] (* Amiram Eldar, Nov 30 2019 *)
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CROSSREFS
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KEYWORD
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nonn,base,less
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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