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A333492 Position of first appearance of n in A271410 (LCM of binary indices).

%I A333492 #9 Mar 29 2020 05:19:40
%S A333492 1,2,4,8,16,6,64,128,256,18,1024,12,4096,66,20,32768,65536,258,262144,
%T A333492 24,68,1026,4194304,132,16777216,4098,67108864,72,268435456,22,
%U A333492 1073741824,2147483648,1028,65538,80,264,68719476736,262146,4100,144,1099511627776,70,4398046511104
%N A333492 Position of first appearance of n in A271410 (LCM of binary indices).
%C A333492 A binary index of n is any position of a 1 in its reversed binary expansion. The binary indices of n are row n of A048793.
%H A333492 Giovanni Resta, <a href="/A333492/b333492.txt">Table of n, a(n) for n = 1..1000</a>
%e A333492 The sequence together with the corresponding binary expansions and binary indices begins:
%e A333492       1:                 1 ~ {1}
%e A333492       2:                10 ~ {2}
%e A333492       4:               100 ~ {3}
%e A333492       8:              1000 ~ {4}
%e A333492      16:             10000 ~ {5}
%e A333492       6:               110 ~ {2,3}
%e A333492      64:           1000000 ~ {7}
%e A333492     128:          10000000 ~ {8}
%e A333492     256:         100000000 ~ {9}
%e A333492      18:             10010 ~ {2,5}
%e A333492    1024:       10000000000 ~ {11}
%e A333492      12:              1100 ~ {3,4}
%e A333492    4096:     1000000000000 ~ {13}
%e A333492      66:           1000010 ~ {2,7}
%e A333492      20:             10100 ~ {3,5}
%e A333492   32768:  1000000000000000 ~ {16}
%e A333492   65536: 10000000000000000 ~ {17}
%e A333492     258:         100000010 ~ {2,9}
%t A333492 bpe[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
%t A333492 q=Table[LCM@@bpe[n],{n,10000}];
%t A333492 Table[Position[q,i][[1,1]],{i,First[Split[Union[q],#1+1==#2&]]}]
%Y A333492 The version for prime indices is A330225.
%Y A333492 The version for standard compositions is A333225.
%Y A333492 Let q(k) be the binary indices of k:
%Y A333492 - The sum of q(k) is A029931(k).
%Y A333492 - The elements of q(k) are row k of A048793.
%Y A333492 - The product of q(k) is A096111(k).
%Y A333492 - The LCM of q(k) is A271410(k).
%Y A333492 - The GCD of q(k) is A326674(k).
%Y A333492 GCD of prime indices is A289508.
%Y A333492 LCM of prime indices is A290103.
%Y A333492 LCM of standard compositions is A333226.
%Y A333492 Cf. A000120, A066099, A070939, A074761, A076078, A124767, A285572, A324837, A328219, A328451, A331579, A333227.
%K A333492 nonn
%O A333492 1,2
%A A333492 _Gus Wiseman_, Mar 28 2020
%E A333492 Terms a(23) and beyond from _Giovanni Resta_, Mar 29 2020