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Every prefix prime in base 9 (written in base 9).
4

%I #12 Aug 09 2017 00:02:03

%S 2,3,5,7,21,25,32,34,52,58,74,78,212,218,254,322,328,342,344,528,582,

%T 744,782,784,788,2122,2182,2188,2542,2548,3224,3282,3422,3442,3444,

%U 5282,7448,7844,7884,21222,21822,25428,25484,32242,32248,34224,34228,34422,34442

%N Every prefix prime in base 9 (written in base 9).

%H Nathaniel Johnston, <a href="/A024769/b024769.txt">Table of n, a(n) for n = 1..68</a> (full sequence)

%p s:=[1,2,4,5,7,8]: a:=[[2],[3],[5],[7]]: l1:=1: l2:=5: do for j from l1 to l2 do for k from 1 to 6 do d:=[s[k],op(a[j])]: if(isprime(op(convert(d, base, 9, 9^nops(d)))))then a:=[op(a), d]: fi: od: od: l1:=l2+1: l2:=nops(a): if(l1>l2)then break: fi: od: for j from 1 to nops(a) do printf("%d, ", op(convert(a[j],base,10,10^nops(a[j])))); od: # _Nathaniel Johnston_, Jun 21 2011

%K nonn,base,easy,fini,full

%O 1,1

%A _David W. Wilson_

%E Ends at a(68) = 3444224222.