

A075766


Numbers k such that A007923(k) is prime.


0



2, 7, 8, 10, 17, 20, 25, 28, 31, 38, 61, 62, 355, 4690, 4772, 8162, 10523, 14716
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OFFSET

1,1


COMMENTS

SDS(355) certified prime with Primo.
No more terms <= 8000.  XU Pingya, May 30 2017


LINKS



PROG

(PARI) isok(n) = my(m=(n*(n+1)/21)%9+1); isprime(sum(k=0, n1, 10^k*((mk1)%9+1))); \\ Michel Marcus, May 30 2017


CROSSREFS



KEYWORD

more,nonn


AUTHOR



EXTENSIONS



STATUS

approved



