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 A179629 Primes p such that p + the sum of its decimal digits + the sum of the squares of its digits is prime. 1
 23, 59, 83, 89, 127, 181, 229, 233, 239, 241, 257, 283, 293, 359, 383, 389, 421, 457, 523, 541, 547, 557, 563, 571, 577, 599, 659, 683, 751, 787, 809, 811, 829, 839, 853, 859, 877, 883, 887, 1021, 1087, 1129, 1151, 1181, 1187, 1217, 1223, 1249, 1279, 1289 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS I suppose that there are infinitely many twin primes in the sequence, e.g., (239,241), (809,811), (1877,1879). LINKS EXAMPLE a(3)=83 since 83+(8+3)+(8^2+3^2) = 83+11+73 = 167 is a prime. PROG (PARI) isok(n) = {if (isprime(n), digs = digits(n, 10); isprime(n + sum(i=1, #digs, digs[i]) + sum(i=1, #digs, digs[i]^2)); , 0; ); } \\ Michel Marcus, Jul 18 2013 CROSSREFS Sequence in context: A043949 A005111 A225550 * A274381 A044125 A044506 Adjacent sequences:  A179626 A179627 A179628 * A179630 A179631 A179632 KEYWORD nonn,base AUTHOR Carmine Suriano, Jul 21 2010 STATUS approved

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Last modified August 10 16:24 EDT 2022. Contains 356039 sequences. (Running on oeis4.)