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A065969
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a(n) = n^2 * Sum_{primes p dividing n} (1 + 1/p^2).
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1
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0, 5, 10, 20, 26, 85, 50, 80, 90, 229, 122, 340, 170, 445, 484, 320, 290, 765, 362, 916, 940, 1093, 530, 1360, 650, 1525, 810, 1780, 842, 3061, 962, 1280, 2308, 2605, 2524, 3060, 1370, 3253, 3220, 3664, 1682, 5965, 1850, 4372, 4356, 4765
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OFFSET
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1,2
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LINKS
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PROG
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(PARI) { for (n=1, 1000, s=0; p=2; while (p<=n, if(n%p == 0, s+=1 + 1/p^2); p=nextprime(p + 1)); write("b065969.txt", n, " ", n^2*s) ) } \\ Harry J. Smith, Nov 05 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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