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A089137 Primes in the progression (n!- m)/m where n advances by 1 and m resets to 1 upon each prime occurrence. 0
5, 23, 59, 719, 5039, 10079, 181439, 907199, 7983359, 479001599, 622702079, 87178291199, 326918591999, 6974263295999, 59281238015999, 1600593426431999, 15205637551103999, 405483668029439999, 5676771352412159999 (list; graph; refs; listen; history; text; internal format)
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: A246607 A116581 A093622 * A098498 A159241 A179094

Adjacent sequences:  A089134 A089135 A089136 * A089138 A089139 A089140

KEYWORD

base,easy,nonn

AUTHOR

Cino Hilliard, Dec 05 2003

STATUS

approved

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Last modified December 13 22:07 EST 2018. Contains 318087 sequences. (Running on oeis4.)