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A179633
Primes p such that p minus sum of integer of square root of its digits is a prime
0
3, 5, 7, 13, 31, 47, 103, 179, 197, 227, 269, 281, 317, 353, 359, 379, 383, 389, 439, 467, 499, 547, 577, 593, 619, 647, 739, 757, 829, 887, 953, 983, 1069, 1097, 1129, 1187, 1193, 1229, 1307, 1367, 1453, 1459, 1489, 1579, 1601, 1627, 1663, 1753, 1783, 1873
OFFSET
1,1
EXAMPLE
n(5)=31 since 31-[int(sqrt(3))+int(sqrt(1))]=31-1-1=29 is prime.
MATHEMATICA
Select[Prime[Range[300]], PrimeQ[#-Total[Floor/@Sqrt[IntegerDigits[#]]]]&] (* Harvey P. Dale, Aug 25 2013 *)
CROSSREFS
Sequence in context: A089740 A191473 A290482 * A047933 A369433 A075557
KEYWORD
nonn,base
AUTHOR
Carmine Suriano, Jul 21 2010
STATUS
approved