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.

A136189 The 3rd-order Zeckendorf array, T(n,k), read by antidiagonals.

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%I A136189 #28 Apr 08 2025 23:24:55
%S A136189 1,2,5,3,8,7,4,12,11,10,6,17,16,15,14,9,25,23,22,21,18,13,37,34,32,31,
%T A136189 27,20,19,54,50,47,45,40,30,24,28,79,73,69,66,58,44,36,26,41,116,107,
%U A136189 101,97,85,64,53,39,29,60,170,157,148,142,125,94,77,57,43,33,88,249,230
%N A136189 The 3rd-order Zeckendorf array, T(n,k), read by antidiagonals.
%C A136189 Rows satisfy this recurrence: T(n,k) = T(n,k-1) + T(n,k-3) for all k>=4.
%C A136189 Except for initial terms, (row 1) = A000930 (column 1) = A020942 (column 2) = A064105 (column 3) = A064106.
%C A136189 As a sequence, the array is a permutation of the natural numbers.
%C A136189 As an array, T is an interspersion (hence also a dispersion).
%H A136189 Clark Kimberling, <a href="https://www.fq.math.ca/Scanned/33-1/kimberling.pdf">The Zeckendorf array equals the Wythoff array</a>, Fibonacci Quarterly 33 (1995) 3-8.
%H A136189 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A136189 Row 1 is the 3rd-order Zeckendorf basis, given by initial terms b(1)=1, b(2)=2, b(3)=3 and recurrence b(k) = b(k-1) + b(k-3) for k>=4. Every positive integer has a unique 3-Zeckendorf representation: n = b(i(1)) + b(i(2)) + ... + b(i(p)), where |i(h)-i(j)| >= 3. Rows of T are defined inductively: T(n,1) is the least positive integer not in an earlier row. T(n,2) is obtained from T(n,1) as follows: if T(n,1) = b(i(1)) + b(i(2)) + ... + b(i(p)), then T(n,k+1) = b(i(1+k)) + b(i(2+k)) + ... + b(i(p+k)) for k=1,2,3,... .
%F A136189 A(n, k) = A000930(k)*A202342(n) + A000930(k-2)*A136495(n) + A000930(k-1)*(n-1) for n > 1. - _Alan Michael Gómez Calderón_, Dec 23 2024
%e A136189 Northwest corner:
%e A136189   1  2  3  4  6  9  13  19 ...
%e A136189   5  8 12 17 25 37  54  79 ...
%e A136189   7 11 16 23 34 50  73 107 ...
%e A136189  10 15 22 32 47 69 101 148 ...
%e A136189  ...
%Y A136189 Cf. A000930, A035513, A134563, A136175, A136495, A202342.
%K A136189 nonn,tabl
%O A136189 1,2
%A A136189 _Clark Kimberling_, Dec 20 2007