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 A386214 #18 Jul 28 2025 03:21:48 %S A386214 1,2,1,3,2,1,5,3,2,1,8,4,3,2,1,13,6,4,3,2,1,21,7,5,4,3,2,1,34,8,8,5,4, %T A386214 3,2,1,55,11,9,6,5,4,3,2,1,89,14,10,10,6,5,4,3,2,1,144,18,12,11,7,6,5, %U A386214 4,3,2,1,233,22,14,12,12,7,6,5,4,3,2,1 %N A386214 Rectangular array, read by descending antidiagonals: (row m) consists of the union, in increasing order, of the numbers in the following set: {k*((m+1)*F(n) + F(n - 1)): k = 1..m, n>=0}, where F = A000045, the Fibonacci numbers, with F(-1)=1 as in A039834. %H A386214 Clark Kimberling (proposer), P. Bruckman and P. L. Mana (solvers), <a href="https://www.fq.math.ca/Scanned/28-4/elementary28-4.pdf">Problem B-657, Disjoint Increasing Sequences</a>, Fibonacci Quarterly, 30 (1990), 375. %e A386214 Corner of the array: %e A386214 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 %e A386214 1 2 3 4 6 7 8 11 14 18 22 29 36 47 58 %e A386214 1 2 3 4 5 8 9 10 12 14 15 18 23 27 28 %e A386214 1 2 3 4 5 6 10 11 12 15 17 18 20 22 24 %e A386214 1 2 3 4 5 6 7 12 13 14 18 20 21 24 26 %e A386214 1 2 3 4 5 6 7 8 14 15 16 21 23 24 28 %e A386214 1 2 3 4 5 6 7 8 9 16 17 18 24 26 27 %e A386214 (row 3) is the union, in increasing order, of these 3 disjoint sequences: %e A386214 (1, 4, 5, 9, 14, 23, 37, 60, 97, 157, ...); %e A386214 (2, 8, 10, 18, 28, 46, 74, 120, 194, ...); %e A386214 (3, 12, 15, 27, 42, 69, 111, 180, 291, ...). %e A386214 All three sequences are multiples of the first. %t A386214 f[n_] := Fibonacci[n]; %t A386214 t[m_] := Table[k ((m+1)*f[n] + f[n - 1]), {k, 1, m}, {n, 0, 30}]; %t A386214 tt = Table[Sort[Flatten[t[m]]], {m, 1, 14}]; %t A386214 Column[tt] (* array *) %t A386214 u[n_, k_] := tt[[n]][[k]]; %t A386214 Table[u[n - k + 1, k], {n, 1, 12}, {k, n, 1, -1}] // Flatten (* sequence *) %Y A386214 Cf. A000045 (row 1), A127218 (row 2, except for initial terms), A000027 (limiting row), A039834. %K A386214 nonn,tabl %O A386214 1,2 %A A386214 _Clark Kimberling_, Jul 15 2025