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a(n) is the least term in A007602 such that the product of digits equals A342950(n) or 0 if no such number exists.
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%I #13 Apr 02 2021 10:42:05

%S 1,2,3,4,5,6,7,8,9,216,7112,135,128,36,3171,432,0,11111391,12712,1184,

%T 175,11111292,1176,111195,624,1171111711,19116,147112,1197,4224,

%U 114192,0,113319,672,384,171171112,735,1296,11872,0,17136,21248,3915,3168,3177111,13932,21672

%N a(n) is the least term in A007602 such that the product of digits equals A342950(n) or 0 if no such number exists.

%e a(10) = 216 as A342950(10) = 12 and 216 is the least number in A007602 that has product of digits 12.

%e a(17) = 0 as A342950(17) = 25 and the only way the product of digits of a number can be 25 is if the number has two 5's and other digits, if any, are 1. Such a number must end in 5. The tens digit can only be 1 or 5, but no possibility gives a multiple of 25.

%Y Cf. A007602, A342950, A342951.

%K nonn,base

%O 1,2

%A _David A. Corneth_, Mar 30 2021