%I A138759
%S A138759 1,2,9,11,14,17,18,19,20,23,27,28,31,36,37,39,40,46,48,49,50,52,59,65,
%T A138759 70,71,72,73,75,85,86,90,93,95,97,101,102,105,106,109,110,111,118,120,
%U A138759 122,123,124,127,128,131,132,133,140,142,145,146,151,152,153,155,159
%N A138759 Indices for which A001203 (continued fraction for Pi) is prime.
%F A138759 k is in A138759 <=> A001203(k) is in A000040
%e A138759 This sequence starts 1,2,9,11,... since the 1st, 2nd, 9th, 11th...
%e A138759 term of sequence A001203 = (3, 7, 15, 1, 292, 1, 1, 1, 2, ...) are primes.
%o A138759 (PARI) default(realprecision,1000); t=contfrac(Pi); for( k=1,#t, isprime(t[k]) 
               & print1(k","))
%Y A138759 Cf. A001203, A005042, A107892, A138758.
%Y A138759 Sequence in context: A073634 A065554 A034042 this_sequence A098934 A043307 
               A049343
%Y A138759 Adjacent sequences: A138756 A138757 A138758 this_sequence A138760 A138761 
               A138762
%K A138759 nonn
%O A138759 1,2
%A A138759 M. F. Hasler (www.univ-ag.fr/~mhasler), Mar 31 2008