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%I #14 Nov 06 2021 11:05:56
%S 0,1,14,195,2200,24013,255969,2687317,27934809,288342379,2960920297,
%T 30285890402,308834717932,3141625339760,31895159990436
%N Number of positive integers with n digits that are the product of two integers ending with 8.
%C a(n) is the number of n-digit numbers in A348548.
%F a(n) < A052268(n).
%F Conjecture: lim_{n->infinity} a(n)/a(n-1) = 10.
%o (Python)
%o def a(n):
%o lo, hi = 10**(n-1), 10**n
%o return len(set(a*b for a in range(8, hi//8+1, 10) for b in range(a, hi//a+1, 10) if lo <= a*b < hi))
%o print([a(n) for n in range(1, 9)]) # _Michael S. Branicky_, Oct 22 2021
%Y Cf. A052268, A348548.
%Y Cf. A346509 (ending with 1), A346629 (ending with 2), A346952 (ending with 3), A347255 (ending with 4), A337855 (ending with 5), A337856 (ending with 6), A348055 (ending with 7).
%K nonn,base,hard,more
%O 1,3
%A _Stefano Spezia_, Oct 22 2021
%E a(9)-a(10) from _Michael S. Branicky_, Oct 22 2021
%E a(11)-a(15) from _Martin Ehrenstein_, Nov 06 2021
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