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%I #10 Dec 15 2017 17:36:45
%S 1,10,21,30,32,40,43,60,61,65,70,81,92,100,102,106,108,130,150,152,
%T 161,172,174,180,183,185,190,210,221,232,240,250,252,270,280,283,285,
%U 292,298,306,310,322,330,354,361,372,376,381,394,400,408,420,423,430,460
%N Numbers n such that (largest digit of n)^(smallest digit of n) + n is prime.
%C No term ends in 9. Conjecture: Let f(x)=(largest digit of x)^(smallest digit of x) + x. There are infinitely many positive integers n such that f(n) and f(n+1) are both prime; see A097387.
%e 1272 is in the sequence because 7^2 + 1272 = 1321, a prime.
%t okQ[n_]:=Module[{idn=IntegerDigits[n]},PrimeQ[Max[idn]^Min[idn]+n]]
%t Select[Range[500],okQ] (* _Harvey P. Dale_, Dec 11 2010 *)
%Y Cf. A054054, A054055, A097385, A097387.
%K base,easy,nonn
%O 1,2
%A _Jason Earls_, Aug 18 2004
%E Corrected by _T. D. Noe_, Oct 25 2006
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