cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A129143 Start with the empty sequence and append in step k the consecutive numbers 2^(k-1) to 2^(k-1)+k-1.

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%I A129143 #6 Sep 08 2022 08:45:30
%S A129143 1,2,3,4,5,6,8,9,10,11,16,17,18,19,20,32,33,34,35,36,37,64,65,66,67,
%T A129143 68,69,70,128,129,130,131,132,133,134,135,256,257,258,259,260,261,262,
%U A129143 263,264,512,513,514,515,516,517,518,519,520,521,1024,1025,1026,1027,1028
%N A129143 Start with the empty sequence and append in step k the consecutive numbers 2^(k-1) to 2^(k-1)+k-1.
%C A129143 Inspired by A127330.
%H A129143 Ivan Neretin, <a href="/A129143/b129143.txt">Table of n, a(n) for n = 1..5151</a>
%e A129143 In step 5 the numbers 2^4 to 2^4+4 are appended: 16, 17, 18, 19, 20.
%t A129143 Table[2^n + k, {n, 0, 10}, {k, 0, n}] // Flatten (* _Ivan Neretin_, Aug 30 2015 *)
%o A129143 (Magma) &cat[ [2^k..2^k+k]: k in [0..11] ];
%Y A129143 Cf. A127330, A129142.
%K A129143 nonn,easy
%O A129143 1,2
%A A129143 _Klaus Brockhaus_, Mar 31 2007