A228575 Pseudoprimes n to base 2 such that n-4, n-2 and n+2 are primes.

645, 656601, 6212361, 18958567881, 287468425245, 626160901281, 1395494019921, 1925525109201, 1960708164801, 1962378065901, 1977370759365, 2788325761551, 3032013857181, 6877227801081, 22298617759881, 30242009317521, 39454593651201, 42401101442001

Offset

1,1

Comments

All numbers in this sequence end in either 5 or 1.

Links

Shyam Sunder Gupta, Table of n, a(n) for n = 1..831

Example

645 is a pseudoprime (base 2) and 641, 643 and 647 are primes.

Crossrefs

Cf. A001567, A057942, A230488, A230489.

Sequence in context: A067845 A057942 A230488 * A250989 A187434 A046020

Adjacent sequences: A228572 A228573 A228574 * A228576 A228577 A228578

Keyword

nonn

Author

Shyam Sunder Gupta, Oct 27 2013

Status

approved