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.
%I A353658 #22 Dec 26 2024 23:35:42 %S A353658 1,2,4,3,6,7,5,9,10,49,8,11,15,51,80,13,12,18,70,83,549,21,14,19,72, %T A353658 114,551,889,34,16,23,77,117,570,892,6094,55,17,26,79,125,572,923, %U A353658 6096,9861,89,20,27,82,128,782,926,6115,9864,67589 %N A353658 Rectangular array by antidiagonals: row k lists the numbers whose Fibonacci-Lucas representation has k terms. %C A353658 The Fibonacci-Lucas representation of n, denoted by FL(n), is defined for n >= 1 as the sum t(1) + t(2) + ... + t(k), where t(1) is the greatest Fibonacci number (A000045(n), with n >= 2) that is <= n, and t(2) is the greatest Lucas number (A000032(n), with n >= 1) that is <= n - t(1), and so on; that is, the greedy algorithm is applied to find successive greatest Fibonacci and Lucas numbers, in alternating order, with sum n. Every positive integer occurs exactly once in the array. %e A353658 Northwest corner: %e A353658 1 2 3 5 8 13 21 34 %e A353658 4 6 9 11 12 14 16 17 %e A353658 7 10 15 18 19 23 26 27 %e A353658 49 51 70 72 77 79 82 88 %e A353658 80 83 114 117 125 128 133 143 %e A353658 549 551 570 572 782 784 803 805 %e A353658 889 892 923 926 1266 1269 1300 1303 %e A353658 6094 6096 6115 6117 6327 6329 6348 6350 %t A353658 fib = Map[Fibonacci, Range[2, 51]]; %t A353658 luc = Map[LucasL, Range[1, 50]]; %t A353658 t = Map[(n = #; fl = {}; f = 0; l = 0; %t A353658 While[IntegerQ[l], n = n - f - l; %t A353658 f = fib[[NestWhile[# + 1 &, 1, fib[[#]] <= n &] - 1]]; %t A353658 l = luc[[NestWhile[# + 1 &, 1, luc[[#]] <= n - f &] - 1]]; %t A353658 AppendTo[fl, {f, l}]]; %t A353658 {Total[#], #} &[Select[Flatten[fl], IntegerQ]]) &, Range[8000]]; %t A353658 Length[t]; %t A353658 u = Table[Length[t[[n]][[2]]], {n, 1, Length[t]}]; %t A353658 Take[u, 150] %t A353658 TableForm[Table[Flatten[Position[u, k]], {k, 1, 8}]] %t A353658 w[k_, n_] := Flatten[Position[u, k]][[n]] %t A353658 Table[w[n - k + 1, k], {n, 8}, {k, n, 1, -1}] // Flatten %t A353658 (* _Peter J. C. Moses_, May 04 2022 *) %Y A353658 Cf. A000032, A000045, A007895, A116543, A353655, A353656, A353659. %K A353658 nonn,tabl %O A353658 1,2 %A A353658 _Clark Kimberling_, May 04 2022