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 A141288 a(0)=1. a(n) = smallest positive multiple of a(n-1) such that a(n) contains the binary representation of n at least once somewhere within its binary representation. 1
 1, 1, 2, 6, 12, 84, 252, 252, 504, 2520, 17640, 52920, 52920, 52920, 52920, 476280, 952560, 952560, 4762800, 61916400, 185749200, 928746000, 928746000, 928746000, 928746000, 4643730000, 13931190000, 13931190000, 13931190000, 13931190000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Table of n, a(n) for n=0..29. EXAMPLE 6 in binary is 110. Checking the multiples of a(5)=84: 1*84 = 84 = 1010100 in binary. 110 does not occur. 2*84 = 168 = 10101000 in binary. 110 does not occur. But 3*84 = 252 = 11111100 in binary. 110 occurs in this like so: 1111(110)0. So a(6) = 252. MAPLE contai := proc(a, n) verify(convert(n, base, 2), convert(a, base, 2), sublist) ; end: A141288 := proc(n) option remember; local k ; if n= 0 then 1; else for k from 1 do if contai(k*procname(n-1), n) then RETURN( k*procname(n-1) ) ; fi; od: fi; end: seq(A141288(n), n=0..40) ; # R. J. Mathar, Feb 19 2009 CROSSREFS Sequence in context: A226178 A129085 A274941 * A038787 A144098 A259140 Adjacent sequences: A141285 A141286 A141287 * A141289 A141290 A141291 KEYWORD base,nonn AUTHOR Leroy Quet, Aug 01 2008 EXTENSIONS Extended by R. J. Mathar, Feb 19 2009 STATUS approved

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Last modified September 13 10:14 EDT 2024. Contains 375904 sequences. (Running on oeis4.)