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Smallest prime larger than 2^n whose digits begin with those of 2^n.
1

%I #6 Jun 24 2014 01:08:23

%S 11,23,41,83,163,3203,641,1283,25601,51203,10243,20483,40961,81929,

%T 163841,327689,6553621,1310723,2621447,5242883,10485767,20971529,

%U 41943049,838860817,167772161,335544323,6710886407,1342177283

%N Smallest prime larger than 2^n whose digits begin with those of 2^n.

%e a(5) = 3203 with leading digits 32 = 2^5.

%t f[n_] := For[x=10, True, x*=10, For[y=0, y<x, y++, If[PrimeQ[x*n+y], Return[x*n+y]]]]; a[n_] := f[2^n]

%Y Cf. A068841.

%K nonn,base

%O 0,1

%A _Amarnath Murthy_, Mar 10 2002

%E Edited by _Dean Hickerson_, Jun 09 2002