

A078305


Numbers n such that A004154(n)  1 is prime.


4



3, 4, 5, 6, 7, 13, 14, 19, 20, 28, 37, 99, 100, 108, 141, 304, 442, 682
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OFFSET

1,1


COMMENTS

Some of the larger entries may only correspond to probable primes.


LINKS

Table of n, a(n) for n=1..18.


MATHEMATICA

f[n_] := n!/10^Sum[ Floor[n/5^k], {k, 1, Log[10, n] + 1}]; Do[ If[ PrimeQ[ f[n]  1], Print[n]], {n, 1, 750}]


CROSSREFS

Cf. A004154, A078154, A078203, A078190.
Sequence in context: A052002 A247636 A070916 * A235324 A330373 A072599
Adjacent sequences: A078302 A078303 A078304 * A078306 A078307 A078308


KEYWORD

nonn


AUTHOR

Cino Hilliard, Dec 23 2002


EXTENSIONS

Extended by Robert G. Wilson v and Jason Earls, Dec 24 2002


STATUS

approved



