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%I #26 Sep 08 2022 08:45:55
%S 1,11,12,13,15,16,18,19,20,21,23,25,27,29,30,31,32,34,35,37,43,45,50,
%T 51,52,53,54,56,57,58,59,61,65,70,72,73,75,78,79,81,85,87,89,91,92,95,
%U 97,98,101,102,104,106,110,120,140,160,200,201,203,205,209,210,223,225,230,232
%N Numbers k such that (sum of the decimal digits of k) + (product of the decimal digits of k) is prime.
%H Robert Israel, <a href="/A185300/b185300.txt">Table of n, a(n) for n = 1..10000</a>
%e 236 is in the sequence because 2 + 3 + 6 + 2*3*6 = 11 + 36 = 47 is prime.
%p A007953 := proc(n) add(d,d=convert(n,base,10)) ; end proc:
%p A007954 := proc(n) mul(d,d=convert(n,base,10)) ; end proc:
%p isA185300 := proc(n) isprime(A007953(n)+A007954(n)) ; end proc:
%p for n from 1 to 300 do if isA185300(n) then printf("%a,",n) ; end if; end do: # _R. J. Mathar_, Feb 08 2011
%o (Magma) [n: n in [1..232] | IsPrime(&+Intseq(n)+&*Intseq(n))]; // _Bruno Berselli_, Aug 02 2012
%o (PARI) is(n)=my(d=digits(n)); isprime(vecsum(d)+vecprod(d)) \\ _Charles R Greathouse IV_, Jun 06 2017
%Y Cf. A007953, A007954.
%K nonn,base,easy
%O 1,2
%A _Michel Lagneau_, Feb 03 2011