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A179546
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a(n) = p^2*(p + 3)/2, where p = prime(n).
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1
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10, 27, 100, 245, 847, 1352, 2890, 3971, 6877, 13456, 16337, 27380, 36982, 42527, 55225, 78652, 107911, 119072, 157115, 186517, 202502, 255881, 296227, 364366, 470450, 530452, 562277, 629695, 665336, 740602, 1048385, 1149787, 1313830
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OFFSET
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1,1
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COMMENTS
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Old name was "The first a(n) numbers killed in a Sieve of Eratosthenes".
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LINKS
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FORMULA
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p^2*(p+3)/2 as p runs through the primes. [R. J. Mathar, Aug 05 2010]
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EXAMPLE
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2: 2*2 + 2*3 = 2*(3*4/2-1) = 10;
3: 3*2 + 3*3 + 3*4 = 3*(4*5/2-1) = 27;
5: 5*2 + 5*3 + 5*4 + 5*5 + 5*6 = 5*(6*7/2-1) = 100;
7: 7*2 + 7*3 + 7*4 + 7*5 + 7*6 + 7*7 + 7*8 = 7*(8*9/2-1) = 245; etc.
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MATHEMATICA
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Table[Prime[n]^2 (Prime[n] + 3)/2, {n, 40}] (* Bruno Berselli, Feb 03 2015 *)
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PROG
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(PARI) vector(50, n, p=prime(n); p^2*(p+3)/2) \\ Michel Marcus, Feb 03 2015
(Magma) [p^2*(p+3)/2: p in PrimesUpTo(200)]; // Bruno Berselli, Feb 03 2015
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Name and example rephrased and offset changed by Editors of the OEIS, Feb 03 2015
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STATUS
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approved
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