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A162401 a(n) is the largest integer whose square, when represented in binary, is a substring within the binary representation of n. 2

%I #16 Jun 16 2018 19:52:04

%S 1,1,1,2,1,1,1,2,3,1,1,2,1,1,1,4,2,3,3,2,1,1,1,2,5,1,1,2,1,1,1,4,4,2,

%T 2,6,3,3,3,2,3,1,1,2,1,1,1,4,7,5,5,2,1,1,1,2,5,1,1,2,1,1,1,8,4,4,4,2,

%U 2,2,2,6,6,3,3,3,3,3,3,4,9,3,3,2,1,1,1,2,5,1,1,2,1,1,1,4,4,7,7

%N a(n) is the largest integer whose square, when represented in binary, is a substring within the binary representation of n.

%C A162400(n) = A162401(n)^2.

%H Alois P. Heinz, <a href="/A162401/b162401.txt">Table of n, a(n) for n = 1..16384</a> (first 10000 terms from Robert G. Wilson v)

%t f[n_] := Block[{k = Floor@ Sqrt@ n, s = ToString@ FromDigits@ IntegerDigits[n, 2]}, While[ StringPosition[s, ToString@ FromDigits@ IntegerDigits[k^2, 2]] == {}, k-- ]; k]; Array[f, 105] (* _Robert G. Wilson v_, Jul 16 2009 *)

%Y Cf. A162400.

%K base,nonn,look

%O 1,4

%A _Leroy Quet_, Jul 02 2009

%E a(16) correction and more terms from _Robert G. Wilson v_, Jul 16 2009

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Last modified April 23 05:16 EDT 2024. Contains 371906 sequences. (Running on oeis4.)