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A131959 Numbers n such that prod(k=1,n,prime(k)^prime(n-k+1)) + 1 is prime. 1
1, 2, 3, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A131958 gives the corresponding primes.

LINKS

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

EXAMPLE

(2^5)*(3^3)*(5^2) + 1 = 21601 is the prime for the term 3.

CROSSREFS

Cf. A131958.

Sequence in context: A196303 A048979 A088332 * A202688 A021046 A138180

Adjacent sequences:  A131956 A131957 A131958 * A131960 A131961 A131962

KEYWORD

hard,nonn,more

AUTHOR

Rick L. Shepherd, Aug 01 2007

STATUS

approved

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Last modified May 29 14:18 EDT 2020. Contains 334700 sequences. (Running on oeis4.)