A089137 Primes in the progression (n!- m)/m where n advances by 1 and m resets to 1 upon each prime occurrence.

5, 23, 59, 719, 5039, 10079, 181439, 907199, 7983359, 479001599, 622702079, 87178291199, 326918591999, 6974263295999, 59281238015999, 1600593426431999, 15205637551103999, 405483668029439999, 5676771352412159999

Offset

1,1

Links

Table of n, a(n) for n=1..19.

Example

n=5,m=1 (5!-1)/1 = 119=7*17 not prime m advances to 2.
n=5,m=2 (5!-2)/2 = 118/2 = 59 prime keep it.

Prog

(PARI) nfactm2d2(n, m) = { for(x=1, n, for(k=1, m, y=floor((x!- k)/k); if(isprime(y), print1(y", "); break) ) ) }

Crossrefs

Sequence in context: A116581 A337750 A093622 * A361917 A362338 A098498

Adjacent sequences: A089134 A089135 A089136 * A089138 A089139 A089140

Keyword

base,easy,nonn

Author

Cino Hilliard, Dec 05 2003

Status

approved