

A118559


Lucky numbers for which both the sum of the digits and the product of the digits is also a lucky number.


1



1, 3, 7, 9, 111, 133, 135, 171, 331, 357, 535, 537, 553, 717, 735, 11113, 11137, 11173, 11371, 11373, 11535, 11731, 11911, 13113, 13117, 13179, 13317, 13335, 13371, 13515, 13533, 13551, 15333, 15511, 15531, 17313, 17391, 17737, 17913, 17997
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OFFSET

1,2


LINKS



EXAMPLE

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.


MATHEMATICA

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 *)


CROSSREFS



KEYWORD

base,nonn


AUTHOR

Luc Stevens (lms022(AT)yahoo.com), May 07 2006


EXTENSIONS

Corrected and extended by Adam Panagos (adam.panagos(AT)gmail.com) and Robert G. Wilson v, May 10 2006


STATUS

approved



