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

19, 29, 31, 47, 59, 89, 131, 197, 151, 227, 179, 269, 239, 359, 311, 467, 379, 569, 439, 659, 479, 719, 547, 821, 571, 857, 607, 911, 619, 929, 631, 947, 647, 971, 739, 1109, 787, 1181, 811, 1217, 839, 1259, 859, 1289, 967, 1451, 1039, 1559, 1259, 1889, 1319

Offset

1,1

Links

Table of n, a(n) for n=1..51.

Example

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

Maple

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

Crossrefs

Cf. A000040, A141468.

Sequence in context: A052260 A067833 A135170 * A370139 A139539 A191047

Adjacent sequences: A173956 A173957 A173958 * A173960 A173961 A173962

Keyword

nonn

Author

Juri-Stepan Gerasimov, Mar 03 2010

Extensions

Corrected and extended by R. J. Mathar, Mar 29 2010

Status

approved