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A213739
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Numbers n such that n and n^2 are sums of two successive primes.
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2
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12, 24, 42, 84, 90, 120, 204, 240, 372, 410, 456, 600, 630, 740, 762, 852, 882, 978, 1088, 1140, 1148, 1272, 1460, 1518, 1584, 1620, 1656, 1758, 1770, 1878, 1900, 1960, 2052, 2316, 2562, 2688, 2886, 2992, 3570, 3634, 3678, 3738, 3750, 3924, 4170, 4314, 4906
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OFFSET
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1,1
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COMMENTS
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First terms not multiple of 6: 410, 740, 1088, 1148, 1460, 1900, 1960.
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LINKS
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EXAMPLE
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12=5+7, 144=71+73;
24=11+13, 576=283+293;
42=19+23, 1764=881+883.
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MATHEMATICA
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Reap[ Do[ If[ (p=NextPrime[n/2, -1]; p+NextPrime[p] == n) && (q=NextPrime[n^2/2, -1]; q+NextPrime[q] == n^2) , Sow[n]], {n, 2, 5000, 2}]][[2, 1]] (* Jean-François Alcover, Jul 17 2012 *)
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PROG
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(PARI) p=2; forprime(q=3, 1e3, n=p+q; if(precprime(n^2/2)+nextprime((n^2+1)/2)==n^2, print1(n", ")); p=q) \\ Charles R Greathouse IV, Jun 21 2012
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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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