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A121914 Numbers n such that (partial sums of n times (n 1's)) + 1 is prime; or n such that Sum_{k=1..n} A053422(k) + 1 is prime. 0
1, 4, 15, 31, 424, 895 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also, numbers n such that (20+20*(9*n-1)*10^n-81*(n^2+n))/1458 + 1 is prime.

LINKS

Table of n, a(n) for n=1..6.

CROSSREFS

Sequence in context: A031012 A188075 A322740 * A321490 A270710 A110341

Adjacent sequences:  A121911 A121912 A121913 * A121915 A121916 A121917

KEYWORD

more,nonn

AUTHOR

Jason Earls, Sep 02 2006

STATUS

approved

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Last modified January 18 23:05 EST 2019. Contains 319282 sequences. (Running on oeis4.)