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%I #5 Mar 30 2012 18:39:53
%S 1,41,81,256,2810,19680,131516,1812049
%N a(n) = k smallest exponent of N = 2^k of first prime(1) = 2 where string "p(1) ... p(n)" appears in the decimal representation of N (n=1,2,...).
%D Julian Havil, Impossible?: Surprising Solutions to Counterintuitive Conundrums, Princeton University Press 2008
%e n=1: 2^1 = 2
%e n=2: 2^41 = 2199023255552, "23" appears on decimals 6-7
%e n=3: 2^81 = 2417851639229258349412352, "235" appears on decimals 22-24
%e n=4: 2^256 has 78 decimals, "2357" appears on decimals 20-23
%e 2^256 = 115792089237316195423570985008687907853269984665640564039457584007913129639936
%Y Cf. A000079, A018802, A171132, A171242, A171489, A171652, A171768
%K nonn,base
%O 1,2
%A Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Feb 21 2010
%E Extended and edited by _Hans Havermann_, Mar 20 2010
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