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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.

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`%I #8 Oct 04 2015 00:02:18
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`%S 1,1,2,6,12,84,252,252,504,2520,17640,52920,52920,52920,52920,476280,
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`%T 952560,952560,4762800,61916400,185749200,928746000,928746000,
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`%U 928746000,928746000,4643730000,13931190000,13931190000,13931190000,13931190000
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`%N 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.
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`%e 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.
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`%p 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
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`%K base,nonn
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`%O 0,3
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`%A _Leroy Quet_, Aug 01 2008
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`%E Extended by _R. J. Mathar_, Feb 19 2009
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