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%I #11 Nov 18 2019 03:21:31
%S 1,3,7,9,111,133,135,171,331,357,535,537,553,717,735,11113,11137,
%T 11173,11371,11373,11535,11731,11911,13113,13117,13179,13317,13335,
%U 13371,13515,13533,13551,15333,15511,15531,17313,17391,17737,17913,17997
%N Lucky numbers for which both the sum of the digits and the product of the digits is also a lucky number.
%H Amiram Eldar, <a href="/A118559/b118559.txt">Table of n, a(n) for n = 1..10000</a>
%e 133 is in the sequence because: (1) it is a lucky number, (2) the sum of its digits 1+3+3=7 is a lucky number, (3) the product of its digits 1*3*3=9 is a lucky number.
%t lst = Range[1, 19172, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; Select[lst, MemberQ[lst, Plus @@ IntegerDigits@# ] && MemberQ[lst, Times @@ IntegerDigits@# ] &] (* _Robert G. Wilson v_ *)
%Y Cf. A000959, A007953, A007954.
%K base,nonn
%O 1,2
%A Luc Stevens (lms022(AT)yahoo.com), May 07 2006
%E Corrected and extended by Adam Panagos (adam.panagos(AT)gmail.com) and _Robert G. Wilson v_, May 10 2006