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%I #17 Sep 08 2022 08:45:17
%S 9,33,69,81,83,107,113,117,131,147,161,173,177,179,201,213,219,221,
%T 249,273,287,291,333,351,383,393,407,423,429,443,449,459,471,501,507,
%U 527,537,539,543,557,579,603,617,633,639,641,659,677,683,689,711,747
%N Numbers k such that the string 10100k is the decimal expansion of a prime number.
%H Daniel Starodubtsev, <a href="/A103602/b103602.txt">Table of n, a(n) for n = 1..10000</a>
%e 9, 107 and 147 are in the sequence because 101009, 10100107 and 10100147 are prime.
%o (Magma) [ n: n in [1..800] | IsPrime(Seqint(Intseq(n) cat [0, 0, 1, 0, 1])) ];
%K base,nonn
%O 1,1
%A _Parthasarathy Nambi_, Mar 23 2005