%I #11 Aug 03 2012 10:28:35
%S 23,29,31,47,59,61,71,79,109,113,127,151,157,167,179,191,223,229,233,
%T 239,241,251,271,283,317,349,359,367,373,379,383,431,433,439,457,463,
%U 467,479,487,491,499,503,509,541,563,599,607,631,701,719,727,733,743,751,757
%N Primes that can be written in binary representation as a concatenation of odd primes.
%C Subsequence of A090423.
%e 31 is 11111 in binary, 11 is 3 in decimal, 111 is 7, partition exists: 11_111, so 31 is in the sequence.
%o (Python)
%o # oddPrimes = [3, ... , 757]
%o def tryPartioning(binString): # First digit is not 0
%o if binString=='10':
%o return 0
%o l = len(binString)
%o for t in range(2, l-1):
%o substr1 = binString[:t]
%o if (int('0b'+substr1,2) in oddPrimes) or (t>=4 and tryPartioning(substr1)):
%o substr2 = binString[t:]
%o if substr2[0]!='0':
%o if (int('0b'+substr2,2) in oddPrimes) or (l-t>=4 and tryPartioning(substr2)):
%o return 1
%o return 0
%o for p in oddPrimes:
%o if tryPartioning(bin(p)[2:]):
%o print p,
%Y Cf. A090423.
%K nonn,base
%O 1,1
%A _Alex Ratushnyak_, Aug 03 2012
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