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A065145 Smallest prime that begins with the n-th square in decimal notation.

%I A065145 #7 May 17 2018 05:31:12
%S A065145 11,41,97,163,251,367,491,641,811,1009,1213,1447,1693,19603,2251,
%T A065145 25601,2897,32401,3613,4001,44101,48407,5297,57601,6257,6761,7297,
%U A065145 7841,8419,9001,9613,10243,10891,115601,12251,12967,13691,14447,15217,16001
%N A065145 Smallest prime that begins with the n-th square in decimal notation.
%H A065145 Robert Israel, <a href="/A065145/b065145.txt">Table of n, a(n) for n = 1..10000</a>
%F A065145 a(n) = A030665(n^2). - _Robert Israel_, May 16 2018
%p A065145 f:= proc(n) local d,m,r;
%p A065145   for d from 1 do
%p A065145    for m from 1 to 10^d-1 by 2 do
%p A065145     r:= 10^d*n^2 + m;
%p A065145     if isprime(r) then return r fi
%p A065145   od od
%p A065145 end proc:
%p A065145 map(f, [$1..100]); # _Robert Israel_, May 16 2018
%Y A065145 Cf. A030665, A062584, A000290, A000040, A065144.
%K A065145 base,nonn
%O A065145 1,1
%A A065145 _Reinhard Zumkeller_, Oct 17 2001