A107794 Numbers n such that both n plus its first digit and n minus its first digit are primes.

12, 18, 21, 34, 65, 67, 81, 92, 98, 102, 108, 138, 150, 180, 192, 198, 225, 231, 279, 310, 314, 334, 350, 356, 370, 376, 386, 405, 435, 453, 483, 495, 504, 552, 582, 607, 613, 625, 637, 647, 653, 667, 726, 750, 780, 819, 831, 920, 928, 938, 962, 1020, 1032, 1050

Offset

1,1

Comments

Average of pairs: 66,3255,3465,6696,6786,6954,9429,31725,34845,60096,...

Links

Table of n, a(n) for n=1..54.

Mathematica

Select[ Range[1060], PrimeQ[ # + IntegerDigits[ # ][[1]]] && PrimeQ[ # - IntegerDigits[ # ][[1]]] &]

Crossrefs

Intersection of A107835 & A107836.

Sequence in context: A171674 A247624 A031207 * A280014 A359929 A162151

Adjacent sequences: A107791 A107792 A107793 * A107795 A107796 A107797

Keyword

base,nonn

Author

Eric Angelini and Robert G. Wilson v, Jun 14 2005

Status

approved