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A069262
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a(n) = 4*prime(n)^2.
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4
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16, 36, 100, 196, 484, 676, 1156, 1444, 2116, 3364, 3844, 5476, 6724, 7396, 8836, 11236, 13924, 14884, 17956, 20164, 21316, 24964, 27556, 31684, 37636, 40804, 42436, 45796, 47524, 51076, 64516, 68644, 75076, 77284, 88804, 91204, 98596
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OFFSET
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1,1
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COMMENTS
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Previous name was: Numbers n such that sum(d|n,(-1)^d) = 3.
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LINKS
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FORMULA
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a(n) = 4*prime(n)^2 = 4*A001248(n).
Numbers k such that A048272(k) = -3.
Sum_{n>=1} 1/a(n) = P(2)/4, where P is the prime zeta function. - Amiram Eldar, Dec 19 2020
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MATHEMATICA
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PROG
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(PARI) lista(nn) = {forprime(p=2, nn, print1(4*p^2, ", ")); } \\ Altug Alkan, Mar 23 2016
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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