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%I #5 Apr 16 2014 00:40:28
%S 7,43,61,151,223,241,313,331,421,1033,1123,1213,1231,1321,2113,2131,
%T 2221,2311,3121,4111,5011,10141,11113,11131,11311,12211,14011,21121,
%U 21211,22111,30211,101221,102121,111121,111211,112111,131011,310111
%N Smallest primes in growing order where the parts of compositions of integer 7 used as decimal digits enable primes.
%C See comments and references of A176251.
%C 15 partitions of integer 7: 7, 1+6, 2+5, 3+4, 1+1+5, 1+2+4, 1+3+3, 2+2+3, 1+1+1+4, 1+1+2+3, 1+2+2+2, 1+1+1+1+3, 1+1+1+2+2, 1+1+1+1+1+2, 1+1+1+1+1+1+1
%C partition 2+5 enables no primes
%C 41 compositions (the order matters) of integer 7, which with included zeros enable primes, so this sequence has 41 = prime(13) terms
%C Prime indices (6 primes, 2 squares, 1 cube)
%C 4=2^2, 14, 18, 36=6^2, 48, 53, 65, 67, 82, 174, 188, 198, 202, 216=6^3, 319, 321, 331, 344, 445, 566, 672, 1245, 1346, 1349, 1367, 1460, 1654, 2374, 2385, 2479, 3268, 9696, 9781, 10546, 10552, 10629, 12246, 26809, 93015, 149709, 733339
%e 43 = prime(14), 2nd term
%e 1201111 = prime(93015), 39th term
%e 2011111 = prime(149709), 40th term
%e 11110111 = prime(733339), 41st term
%e Curious 2221 = prime(331) and 331 itself is 7th term of sequence, 1321 = prime(6^3)
%e 4 palindromic primes: 7 = palprime(2^2), 151 = palprime(2^3), 313 = palprime(11), 11311 = palprime(4!)
%Y A000041, A046704, A075177, A091939, A176009, A176251.
%K base,fini,nonn,uned
%O 1,1
%A Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 13 2010