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A179632
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Primes p such that p + the integer part of square root of its digits is a prime.
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1
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2, 5, 11, 19, 67, 101, 109, 127, 163, 457, 557, 587, 593, 599, 613, 647, 677, 823, 857, 877, 941, 971, 1009, 1097, 1187, 1213, 1277, 1291, 1367, 1427, 1453, 1481, 1483, 1543, 1553, 1559, 1663, 1741, 1753, 1783, 1861, 1871, 1873, 1907, 2083, 2267, 2287
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OFFSET
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1,1
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LINKS
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EXAMPLE
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67 is in the sequence since 67 + int(sqrt(6)) + int(sqrt(7)) = 67+2+2 = 71 is prime.
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PROG
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(PARI) isok(n) = {if (isprime(n), digs = digits(n, 10); isprime(n + sum(i=1, #digs, sqrtint(digs[i]))); , 0; ); } \\ Michel Marcus, Jul 18 2013
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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