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Primes p such that p + the integer part of square root of its digits is a prime.
1

%I #6 Jul 18 2013 08:37:55

%S 2,5,11,19,67,101,109,127,163,457,557,587,593,599,613,647,677,823,857,

%T 877,941,971,1009,1097,1187,1213,1277,1291,1367,1427,1453,1481,1483,

%U 1543,1553,1559,1663,1741,1753,1783,1861,1871,1873,1907,2083,2267,2287

%N Primes p such that p + the integer part of square root of its digits is a prime.

%e 67 is in the sequence since 67 + int(sqrt(6)) + int(sqrt(7)) = 67+2+2 = 71 is prime.

%o (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

%K nonn,base

%O 1,1

%A _Carmine Suriano_, Jul 21 2010