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A334679 Numbers k such that k*p is divisible by k+p, where p > 0 and p = A007954(k) = the product of digits of k.

%I A334679 #18 Jul 02 2021 01:54:28
%S A334679 2,4,6,8,24,36,63,456,495,3276,6624,7497,8832,19728,23976,127488,
%T A334679 167328,273525,274995,297675,576975,661248,797769,853776,1323648,
%U A334679 1378272,1491264,1886976,3483648,3679263,3787749,4644864,6386688,7886592,7888896,12841472,15974784,16224768
%N A334679 Numbers k such that k*p is divisible by k+p, where p > 0 and p = A007954(k) = the product of digits of k.
%H A334679 Giovanni Resta, <a href="/A334679/b334679.txt">Table of n, a(n) for n = 1..95</a> (terms < 3.5*10^14)
%e A334679 8 is a term as p = 8 and 8*8 = 64 is divisible by 8+8 = 16.
%e A334679 3276 is a term as p = 3*2*7*6 = 252 and 3276*252 = 825552 is divisible by 3276+252 = 3528.
%e A334679 3787749 is a term as p = 3*7*8*7*7*4*9 = 296352 and 3787749*296352 = 1122506991648 is divisible by 3787749+296352 = 4084101.
%t A334679 Select[Range[10^6], (p = Times @@ IntegerDigits@ #; p > 0 && Mod[# p, # + p] == 0) &] (* _Giovanni Resta_, May 08 2020 *)
%o A334679 (PARI) isok(m) = my(p=vecprod(digits(m))); p && !((m*p) % (m+p)); \\ _Michel Marcus_, May 08 2020
%Y A334679 Cf. A330880, A334803, A007954, A049102, A085124.
%Y A334679 Subsequence of A052382.
%K A334679 nonn,base
%O A334679 1,1
%A A334679 _Scott R. Shannon_, May 08 2020