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a(n) is the numerator of the largest ratio among the A341052(n) ratios for which there exist A341051(n) n-digit integers (the maximum possible) that are in geometric progression.
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%I #15 Dec 30 2021 10:49:25

%S 2,3,3,4,4,5,5,5,5,6,7,7,7,7,8,8,8,9,9,9,10,11,11,11,11,11,12,12,13,

%T 12,13,13,13,14,14,14,15,14,15,15,15,16,16,16,17,17,17,17,18,18,18,18,

%U 18,19,19,19,20,20,20,21,21,21,21,22,21,22,22,22,23,23,23

%N a(n) is the numerator of the largest ratio among the A341052(n) ratios for which there exist A341051(n) n-digit integers (the maximum possible) that are in geometric progression.

%C The numerator of the corresponding largest ratio is the smallest numerator on the n-th row of A341053, hence, a(n) is the 1st term of the n-th row of A341053.

%C The corresponding denominator of these ratios is equal to a(n) - 1.

%C This sequence is not increasing as a(29) = 13 > a(30) = 12.

%F a(n) = T(n,1), 1st term of the n-th row of A341053.

%F a(n) = A350255(n) iff A341052(n) = 1.

%e There exist A341051(9) = 11 integers in the largest possible string with 9-digit numbers that are in geometric progression, and three such strings are obtained with the A341052(9) = 3 distinct following ratios 5/4 > 6/5 > 7/6. The largest ratio is 5/4 and a(9) = 5.

%Y Cf. A341051, A341052, A341053, A350255.

%K nonn,base

%O 1,1

%A _Bernard Schott_, Dec 22 2021

%E More terms from _Jinyuan Wang_, Dec 30 2021