A107799 - OEIS

%I #6 Mar 30 2012 17:26:16

%S 1,2,3,4,5,9,15,17,18,21,24,26,48,87,102,110,143,161,177,345,604,671,

%T 797,927,1008,1346,2491,5140,7942,19798,41539,49943,58202,63958,86538

%N Indices of primes occurring in A107798.

%C Cf. A030284 = Primes whose digits do not appear in previous term, A107798 = Primes whose digits do not appear in two previous terms.

%F a(n)=pi(A030284(n))

%t d=2;e=3;b={2, 3};id[t_]:=IntegerDigits[t];Do[p=Prime[n];If[Intersection[Union[id[d], id[e]], id[p]]=={}, b=Append[b, n];d=e;e=p], {n, 100000}];b

%Y Cf. A030284, A107798.

%K nonn,base

%O 1,2

%A _Zak Seidov_, May 24 2005