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A092344
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a(0)=1; a(n) = sigma_2(n) + sigma_3(n).
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0
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1, 2, 14, 38, 94, 152, 302, 394, 670, 848, 1264, 1454, 2254, 2368, 3346, 3788, 5022, 5204, 7268, 7222, 9744, 10132, 12598, 12698, 17230, 16402, 20632, 21260, 26162, 25232, 33052, 30754, 38814, 38516, 45676, 44644, 57172, 52024, 63550, 63244, 75920, 70604, 89188
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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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G.f.: 1 + Sum_{k>=1} k^2*(k + 1)*x^k/(1 - x^k). - Ilya Gutkovskiy, Mar 17 2017
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MATHEMATICA
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Join[{1}, Table[DivisorSigma[2, n]+DivisorSigma[3, n], {n, 50}]] (* Harvey P. Dale, Feb 05 2020 *)
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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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