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a(n)=m if n belongs to the S_m sequence described in A240521.
8

%I #24 Oct 11 2021 18:52:57

%S 1,1,1,1,3,1,5,1,9,1,3,1,17,5,1,1,33,1,3,9,65,1,7,1,129,17,5,1,13,1,

%T 257,33,513,3,9,1,1025,65,11,1,25,1,17,5,2049,1,129,1,4097,257,33,1,

%U 49,9,21,513,8193,1,7,1,16385,3,65,17,97,1,129,1025,19,1

%N a(n)=m if n belongs to the S_m sequence described in A240521.

%C See comments in A240521.

%e Let n = 30. We have a unique representation of 30 as a product of distinct terms of A050376: 30 = 2*3*5. We write all the terms of A050376 in the interval [2,5]: 2,3,4,5. Under the terms used in the representation of 30 we write 1, under other terms we write 0. After concatenation we obtain the binary number corresponding to 30: 1101. In decimal it is 13. So a(30) = 13.

%e Let n = 60 = 3*4*5. In the interval [3,5] the terms of A050376 are 3,4,5, all of which are used in the representation of 60. So we write 1 under all 3 terms and obtain the binary number 111. In decimal it is 7. So a(60)=7.

%Y Positions of particular values: A050376 (1), A240521 (3), A240522 (5), A240524 (7), A240536 (9), A241024 (11), A241025 (13).

%K nonn

%O 2,5

%A _Vladimir Shevelev_, Apr 07 2014

%E Terms corrected and more terms added, _Peter J. C. Moses_, Apr 18 2014

%E Name revised and other edits by _Peter Munn_, Oct 11 2021