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Numbers with property that each sum any pair of digits is prime.
6

%I #14 Jan 31 2024 18:37:29

%S 11,12,14,16,20,21,23,25,29,30,32,34,38,41,43,47,49,50,52,56,58,61,65,

%T 67,70,74,76,83,85,89,92,94,98,111,112,114,116,121,141,161,203,205,

%U 211,230,250,302,320,411,502,520,611,1111,1112,1114,1116,1121,1141,1161

%N Numbers with property that each sum any pair of digits is prime.

%C Supersequence of A091939. Subsequence of A182175.

%H Vincenzo Librandi, <a href="/A221699/b221699.txt">Table of n, a(n) for n = 1..145</a>

%e Number 203 is a term because 2+3=5, 2+0=2, 3+0=3 (primes).

%t fQ[n_] := Module[{d = IntegerDigits[n]}, Union[PrimeQ[Plus @@@ Union[Subsets[d, {2}]]]] == {True}]; Select[Range[6000], fQ] (* _T. D. Noe_, Jan 24 2013 *)

%t Select[Range[10,1200],AllTrue[Total/@Subsets[IntegerDigits[#],{2}],PrimeQ]&] (* _Harvey P. Dale_, Jan 31 2024 *)

%Y Cf. A172508, A091939, A182175.

%K nonn,base

%O 1,1

%A _Jaroslav Krizek_, Jan 22 2013