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a(n) is the least positive number which yields a multiple of n when its binary digit string, S(n), is read in any numeric base; a(n) is displayed in base 10.
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%I #57 Aug 01 2024 14:11:50

%S 1,6,42,60,139810,126,139620524162,2040,349524,419430,

%T 2537779500750160131246576896002,16380,

%U 44612382091907903486070965589630128805126146,418861572486,146602109610,1048560

%N a(n) is the least positive number which yields a multiple of n when its binary digit string, S(n), is read in any numeric base; a(n) is displayed in base 10.

%C If we consider sequence terms to be character strings, a(n) is A329126(n) read in base 2 and converted to base 10. Based on b-file for A329126.

%C Least k >= 1 such that n divides A329443(k). - _Peter Munn_, Dec 02 2021

%F a(n) <= A329339(n) = 2^A051903(n)*(m^n-1)/(m-1) with m = 2^A268336(n), equality except for n = 10, 14, 15, ... - _M. F. Hasler_, Nov 14 2019

%e The strings S(1), S(2), S(3), ... are 1, 110, 101010, 111100, 100010001000100010, 1111110, ... (A329126); converted from binary to decimal these give the current sequence.

%o (PARI) \\ See A329339. - _M. F. Hasler_, Nov 14 2019

%Y Cf. A329126, A329339, A329338, A067029, A268336, A329443.

%K nonn,base

%O 1,2

%A _N. J. A. Sloane_, Nov 12 2019

%E Definition corrected: not lexicographically earliest string, but smallest binary number. - _M. F. Hasler_, Nov 09 2021

%E Name aligned with new A329126 name by _Peter Munn_, Dec 02 2021