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A128466 Primes of the form ((n+1)^n-1)/n^2 = A060073(n+1). 4
2, 7, 311, 7563707819165039903 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Corresponding numbers n such that ((n+1)^n-1)/n^2 is a prime are listed in A127837(n) = {2, 3, 5, 17, ...}. a(n) are the primes in A060073(n) = (n^(n-1)-1)/(n-1)^2 = {1, 2, 7, 39, 311, 3268, 42799, ...}.

Next term has 15850 = 1+floor((4357*log(4358)-2*log(4357))/log(10)) digits and is too large to include. - M. F. Hasler, May 22 2007

LINKS

Table of n, a(n) for n=1..4.

FORMULA

a(n) = ((A127837(n) + 1)^A127837(n) - 1) / A127837(n)^2.

MATHEMATICA

Select[Table[((n+1)^n-1)/n^2, {n, 500}], PrimeQ]  (* Harvey P. Dale, Apr 30 2011 *)

PROG

(PARI) A128466(n)=A060073(A127837(n)+1) /* see there. --- or: */ forprime(p=1, 10^5, if(ispseudoprime(n=((p+1)^p-1)/p^2), print1(n, ", "))); - M. F. Hasler, May 22 2007

CROSSREFS

Cf. A127837, A037205, A060072, A060073, A058128, A128456

Sequence in context: A128456 A137666 A137665 * A048122 A144787 A118910

Adjacent sequences:  A128463 A128464 A128465 * A128467 A128468 A128469

KEYWORD

nonn

AUTHOR

Alexander Adamchuk, Mar 09 2007

STATUS

approved

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Last modified April 12 18:58 EDT 2021. Contains 342932 sequences. (Running on oeis4.)