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%I #6 Dec 05 2013 19:55:17
%S 1,0,2,1,0,1,2,0,1,1,0,0,2,0,1,0,0,1,1,0,1,0,0,1,1,0,2,1,0,0,2,0,2,0,
%T 0,0,2,0,1,1,0,1,1,0,0,1,0,0,3,0,1,1,0,1,0,0,2,0,0,1,0,0,3,1,0,1,2,0,
%U 2,1,0,0,1,0,1,1,0,0,2,0,2,1,0,0,0,0,0,1,0,0,2,0,1,1,0,0,2,0,3,0,0,1,3,0,1
%N Number of distinct primes obtained by inserting a 1 at all possible places in n. This includes prefixing and suffixing.
%e a(13) = 2 because 13 -> 113, 113, 131 -> 113 and 131 which are both prime.
%t Table[ Count[ PrimeQ[ Union[ FromDigits /@ Table[ Insert[ IntegerDigits[n], 1, j], {j, 1, Floor[ Log[10, n] + 2]}]]], True], {n, 1, 105}]
%Y Cf. A069843, A069844, A069845, A069846, A069847, A069848, A069849, A069850, A069851.
%K base,nonn
%O 1,3
%A _Amarnath Murthy_, Apr 16 2002
%E More terms from _Vladeta Jovovic_, Apr 17 2002
%E Edited by _Robert G. Wilson v_, Apr 18 2002
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