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A217438 Triangle with the chains described in A217287. 7

%I #11 May 02 2020 23:05:17

%S 1,2,3,2,3,3,4,5,4,5,6,7,5,6,7,6,7,7,8,9,10,11,8,9,10,11,9,10,11,10,

%T 11,12,13,14,11,12,13,14,15,12,13,14,15,13,14,15,14,15,15,16,17,16,17,

%U 18,19,20,21,22,23,17,18,19,20,21,22,23,18,19,20,21,22,23,19,20,21,22,23,20,21,22,23,21,22,23

%N Triangle with the chains described in A217287.

%C The length of row n is A217287(n).

%H Michael De Vlieger, <a href="/A217438/b217438.txt">Table of n, a(n) for n = 1..10441</a> (rows 1 <= n <= 1024, flattened)

%H Michael De Vlieger, <a href="/A217438/a217438.png">Plot (n, m)</a> where m is a term in row n of this sequence, for rows 1 <= n <= 1024.

%e These are the first chains of the triangle:

%e 1, 2, 3;

%e 2, 3;

%e 3, 4, 5;

%e 4, 5, 6, 7;

%e 5, 6, 7;

%e 6, 7;

%e 7, 8, 9, 10, 11;

%e 8, 9, 10, 11;

%e 9, 10, 11;

%e 10, 11, 12, 13, 14;

%e ...

%t Block[{nn = 24, r}, r = Array[If[# == 1, 0, Total[2^(PrimePi /@ FactorInteger[#][[All, 1]] - 1)]] &, nn + Ceiling@ Sqrt@ nn]; Array[Block[{k = # + 1, s = r[[#]]}, While[UnsameQ[s, Set[s, BitOr[s, r[[k]] ] ] ], k++]; Range[#, k - 1]] &, nn] ] // Flatten (* _Michael De Vlieger_, May 02 2020 *)

%Y Cf. A217287, A217288, A217289.

%K nonn,tabf

%O 1,2

%A _Lior Manor_, Oct 03 2012

%E Row 1 prepended to match A217287 and edited by _Michael De Vlieger_, May 02 2020.

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Last modified March 28 16:28 EDT 2024. Contains 371254 sequences. (Running on oeis4.)