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%I #14 Oct 19 2015 04:49:44
%S 4,6,10,14,12,14,18,20,25,32,40,42,46,51,56,64,62,72,76,86,86,104,114,
%T 128,132,138,140,150,152,158,164,168,174,180,182,192,194,198,200,212,
%U 225,231,235,242,252,259,265,272,279,282,285,295,312,314,318,332,340,350
%N Composites of the form smallest digit of prime(n) + prime(n).
%e 23 is prime, 2 < 3, and 2 + 23 = 25 (composite) = a(9);
%e 29 is prime, 2 < 9, and 2 + 29 = 31 (prime);
%e 31 is prime, 3 > 1, and 1 + 31 = 32 (composite) = a(10); etc.
%p A054054 := proc(n) min(op(convert(n,base,10)) ) ; end proc: A144592 := proc(n) p := ithprime(n) ; sd := A054054(p) ; if not isprime(p+sd) then printf("%d,",p+sd) ; end if; end proc: seq(A144592(n),n=1..400) ; # _R. J. Mathar_, May 01 2010
%t Select[#+Min[IntegerDigits[#]]&/@Prime[Range[100]],CompositeQ] (* _Harvey P. Dale_, Jun 28 2015 *)
%o (PARI) for(n=1, 1e3, if(isprime(k=if(n, vecmin(digits(prime(n)))) + prime(n)) == 0, print1(k", "))) \\ _Altug Alkan_, Oct 17 2015
%Y Cf. A000040, A002808.
%K nonn,base
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 12 2009
%E Sequence corrected (by adding 235, which had erroneously been omitted) by _Harvey P. Dale_, Feb 08 2009
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