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A063685 Numbers n such that !n + phi(n)-1 is prime. 0
2, 3, 4, 5, 11, 20, 85, 212 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..8.

PROG

(PARI) f(n) = sum(k=0, n-1, k!); for(n=1, 10^6, if(isprime(f(n)+eulerphi(n)-1), print(n)))

CROSSREFS

Cf. A003422.

Sequence in context: A118968 A073528 A116067 * A006481 A118597 A083160

Adjacent sequences:  A063682 A063683 A063684 * A063686 A063687 A063688

KEYWORD

more,nonn

AUTHOR

Jason Earls, Aug 22 2001

STATUS

approved

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Last modified December 5 12:04 EST 2020. Contains 338947 sequences. (Running on oeis4.)