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%I #14 Jan 27 2017 13:10:25
%S 3,5,7,37,43,53,59,73,79,83,97,337,347,349,353,359,367,373,379,383,
%T 389,397,433,439,443,463,557,563,569,577,587,593,599,643,653,659,673,
%U 683,733,739,743,757,773,787,797,839,853,857,859,863,877,883,887,937,953,977
%N Primes with smallest digit odd and prime (i.e., 3, 5 or 7).
%C Primes p such that A054054(p) is in the set {3, 5, 7}. - _Felix Fröhlich_, Jan 26 2017
%H Robert Israel, <a href="/A155034/b155034.txt">Table of n, a(n) for n = 1..10000</a>
%p N:= 4: # to get all terms with <+ N digits
%p for j in [3,5,7] do L[1,j]:= {$j..9}; C[1,j]:= {j} od;
%p for d from 2 to N do
%p for j in [3,5,7] do L[d,j]:= map(t -> $(10*t+j)..(10*t+9), L[d-1,j]) od:
%p C[d,3]:= map(t -> (10*t+3), L[d-1,3]) union map(t ->seq(10*t+j,j=4..9),C[d-1,3]);
%p C[d,5]:= map(t -> (10*t+5), L[d-1,5]) union map(t -> seq(10*t+j,j=6..9),C[d-1,5]);
%p C[d,7]:= map(t -> (10*t+7), L[d-1,7]) union map(t -> seq(10*t+j,j=8..9),C[d-1,7]);
%p od:
%p sort(convert(`union`(seq(seq(select(isprime,C[d,j]),j=[3,5,7]),d=1..N)),list));
%p # _Robert Israel_, Jan 26 2017
%o (PARI) is(n) = ispseudoprime(n) && #setintersect(Set(vecmin(digits(n))), [3, 5, 7])==1 \\ _Felix Fröhlich_, Jan 26 2017
%Y Cf. A000040, A054054.
%K nonn,base,less
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 19 2009
%E Edited by _N. J. A. Sloane_, Jan 24 2009
%E Corrected by _Robert Israel_, Jan 26 2017
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