A092570 - OEIS

A092570

Primes p which become a prime q under transformation of inner bits of binary representation in A092569. In binary representation of p, transformation of inner bits, 1 <-> 0, gives binary representation of q.

2, 3, 5, 7, 11, 13, 17, 19, 29, 31, 37, 43, 53, 59, 79, 83, 89, 103, 109, 113, 151, 157, 173, 191, 193, 211, 227, 233, 269, 277, 281, 307, 311, 337, 347, 349, 359, 367, 379, 389, 401, 409, 419, 421, 431, 457, 461, 487, 491, 499, 523, 569, 599, 607, 617, 653, 659

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..57.

EXAMPLE

307 and 461 are terms because 307_10 = 100110011_2, transformation of inner bits gives 100110011_2 -> 111001101_2 = 461_10.

PROG

(PARI)T(p)={pow2=2; v=binary(p); L=#v-1; forstep(k=L, 2, -1, if(v[k], p-=pow2, p+=pow2); pow2*=2); return(p)};

forprime(p=2, 659, if(isprime(T(p)), print1(p, ", ")))

\\ Washington Bomfim, Jan 18 2011

CROSSREFS