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A095118
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a(n) is the sum of the squares of the divisors of n which are <= sqrt(n).
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1
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1, 1, 1, 5, 1, 5, 1, 5, 10, 5, 1, 14, 1, 5, 10, 21, 1, 14, 1, 21, 10, 5, 1, 30, 26, 5, 10, 21, 1, 39, 1, 21, 10, 5, 26, 66, 1, 5, 10, 46, 1, 50, 1, 21, 35, 5, 1, 66, 50, 30, 10, 21, 1, 50, 26, 70, 10, 5, 1, 91, 1, 5, 59, 85, 26, 50, 1, 21, 10, 79, 1, 130, 1, 5, 35, 21, 50, 50, 1, 110, 91
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,4
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FORMULA
| G.f.: sum(n=1,S, n^2*x^(n^2)/(1-x^n) ) - Joerg Arndt, Jan 30 2011
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EXAMPLE
| The divisors of 12 which are <= sqrt(12) are 1,2,3, so a(12) = 1^2 + 2^2 + 3^2 = 14.
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MATHEMATICA
| a[n_]:=Plus@@(Select[Divisors[n], #^2<=n&]^2)
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CROSSREFS
| Cf. A095119.
Sequence in context: A050349 A083528 A056957 * A100947 A096940 A141345
Adjacent sequences: A095115 A095116 A095117 * A095119 A095120 A095121
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KEYWORD
| nonn
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AUTHOR
| Dean Hickerson (dean.hickerson(AT)yahoo.com), following a suggestion of Leroy Quet May 28 2004
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