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Number of ways writing the n-th 7-smooth number as a product of decimal digits of some other number which has no digits equal to 1.
1

%I #15 Jan 08 2021 08:53:32

%S 1,1,1,2,1,2,1,3,2,1,3,1,1,4,3,2,1,5,1,2,2,2,5,1,6,3,2,2,7,1,1,4,3,3,

%T 2,7,1,9,1,4,3,3,3,9,1,2,1,7,4,5,1,3,8,2,2,13,1,2,5,5,5,1,6,2,12,2,3,

%U 2,12,5,2,7,3,1,1,6,10,4,3,17,2,3,2,7,10,7

%N Number of ways writing the n-th 7-smooth number as a product of decimal digits of some other number which has no digits equal to 1.

%C This sequence is A067734 without the zeros.

%H David A. Corneth, <a href="/A288738/b288738.txt">Table of n, a(n) for n = 1..10000</a>

%Y Cf. A002473, A007602, A067734.

%K nonn,base

%O 1,4

%A _David A. Corneth_, Jun 22 2017