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A078203 Numbers n such that A004154(n) + 1 is prime. 4
1, 2, 3, 5, 6, 14, 15, 24, 74, 191, 222, 276, 2200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..13.

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, 850}]

CROSSREFS

Cf. A004154, A078154, A078190, A078305.

Sequence in context: A218948 A057704 A281382 * A285937 A253647 A131825

Adjacent sequences:  A078200 A078201 A078202 * A078204 A078205 A078206

KEYWORD

nonn,base

AUTHOR

Cino Hilliard, Dec 23 2002

EXTENSIONS

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

"2200" from Don Reble, Jan 12 2006

STATUS

approved

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Last modified March 2 05:52 EST 2021. Contains 341742 sequences. (Running on oeis4.)