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1,2
Also, numbers n such that (20+20*(9*n-1)*10^n-81*(n^2+n))/1458 + 1 is prime.
Table of n, a(n) for n=1..6.
Sequence in context: A031012 A188075 A322740 * A321490 A270710 A110341
Adjacent sequences: A121911 A121912 A121913 * A121915 A121916 A121917
more,nonn
Jason Earls, Sep 02 2006
approved