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A301944 Number of primes of the form b^2 + 1 for b <= 10^n that end in 7. 1

%I

%S 2,13,68,560,4418,35953,304340,2636531,23265760,208241341,1884492541

%N Number of primes of the form b^2 + 1 for b <= 10^n that end in 7.

%F a(n) + A301943(n) + 2 = A206709(n).

%e 17, 37, 197, 257, 577, 677, 1297, 2917, 3137, 4357, 5477, 7057 and 8837 are primes; so a(2) = 13.

%Y Cf. A002496, A206709, A301943.

%K nonn,base,more

%O 1,1

%A _Seiichi Manyama_, Mar 29 2018

%E a(10)-a(11) from _Jinyuan Wang_, Feb 24 2020

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Last modified July 10 12:34 EDT 2020. Contains 335576 sequences. (Running on oeis4.)