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A173959 List of primes p1 and p2 such that 3*p1 - 2 = 2*p2 - 3 is nonprime. 0

%I

%S 19,29,31,47,59,89,131,197,151,227,179,269,239,359,311,467,379,569,

%T 439,659,479,719,547,821,571,857,607,911,619,929,631,947,647,971,739,

%U 1109,787,1181,811,1217,839,1259,859,1289,967,1451,1039,1559,1259,1889,1319

%N List of primes p1 and p2 such that 3*p1 - 2 = 2*p2 - 3 is nonprime.

%e a(1)=19, a(2)=29 because 3*19 - 2 = 2*29 - 3 = 55.

%p for i from 1 to 400 do p :=ithprime(i) ; q := (3*p+1)/2 ; if type(q,'integer') then if isprime(q) then if not isprime(3*p-2) then printf("%d,%d,",p,q) ; end if; end if; end if; end do: # _R. J. Mathar_, Mar 29 2010

%Y Cf. A000040, A141468.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Mar 03 2010

%E Corrected and extended by _R. J. Mathar_, Mar 29 2010

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Last modified December 13 17:17 EST 2019. Contains 329970 sequences. (Running on oeis4.)