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A344477 Primes that occur as p - (digit product of p) for p in A228139.

%I A344477 #9 May 21 2021 08:05:48
%S A344477 11,17,19,31,37,59,113,173,179,193,199,211,227,233,239,241,257,263,
%T A344477 307,311,317,331,383,389,397,419,439,479,499,521,547,563,571,577,613,
%U A344477 617,659,691,719,733,1117,1153,1171,1193,1201,1213,1279,1319,1399,1447,1483,1493,1511,1531,1543,1609,1871
%N A344477 Primes that occur as p - (digit product of p) for p in A228139.
%C A344477 Terms are unique and in numerical order.
%C A344477 There are terms that correspond to more than one member of A228139, such as 17 = 23-2*3 = 89-8*9.
%H A344477 Robert Israel, <a href="/A344477/b344477.txt">Table of n, a(n) for n = 1..10000</a>
%e A344477 a(5) = 37 is a term because 41 is prime with no digit 0 and 37 = 41-4*1.
%p A344477 d:= 4: # to get terms with at most d digits
%p A344477 M:= 10^d + 9^d:
%p A344477 f:= proc(n) local L,v;
%p A344477   L:= convert(n,base,10);
%p A344477   if member(0,L) then return NULL fi;
%p A344477   if isprime(n) then
%p A344477     v:= n - convert(L,`*`);
%p A344477     if isprime(v) then v fi
%p A344477   fi
%p A344477 end proc:
%p A344477 sort(convert(select(`<`,map(f, {seq(i,i=11..M,2)}),10^d),list));
%Y A344477 Cf. A228139, A344466.
%K A344477 nonn,base
%O A344477 1,1
%A A344477 _J. M. Bergot_ and _Robert Israel_, May 20 2021