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.

A265159 Rectangular array A read by upward antidiagonals in which the entry in row n and column k is defined by A(n,k) = 5 + 9*A005836(2^(k - 1)*(2 n - 1)), n,k >= 1.

Original entry on oeis.org

5, 32, 14, 86, 95, 41, 113, 257, 284, 122, 248, 338, 770, 851, 365, 275, 743, 1013, 2309, 2552, 1094, 329, 824, 2228, 3038, 6926, 7655, 3281, 356, 986, 2471, 6683, 9113, 20777, 22964, 9842, 734, 1067, 2957, 7412, 20048, 27338, 62330, 68891, 29525
Offset: 1

Views

Author

L. Edson Jeffery, Dec 03 2015

Keywords

Comments

Conjecture 1: The array contains without duplication all possible "block numbers" defined in A265100.

Examples

			Array A begins:
.      5    14    41    122    365    1094    3281     9842    29525
.     32    95   284    851   2552    7655   22964    68891   206672
.     86   257   770   2309   6926   20777   62330   186989   560966
.    113   338  1013   3038   9113   27338   82013   246038   738113
.    248   743  2228   6683  20048   60143  180428   541283  1623848
.    275   824  2471   7412  22235   66704  200111   600332  1800995
.    329   986  2957   8870  26609   79826  239477   718430  2155289
.    356  1067  3200   9599  28796   86387  259160   777479  2332436
.    734  2201  6602  19805  59414  178241  534722  1604165  4812494
		

Crossrefs

Programs

  • Mathematica
    (* Array: *)
    a005836[1] := 0; a005836[n_] := If[OddQ[n], 3*a005836[Floor[(n + 1)/2]], a005836[n - 1] + 1]; a265159[n_, k_] := 5 + 9*a005836[2^(k - 1)*(2 n - 1)]; Grid[Table[a265159[n, k], {n, 9}, {k, 9}]]
    (* Array antidiagonals flattened: *)
    a005836[1] := 0; a005836[n_] := If[OddQ[n], 3*a005836[Floor[(n + 1)/2]], a005836[n - 1] + 1]; a265159[n_, k_] := 5 + 9*a005836[2^(k - 1)*(2 n - 1)]; Flatten[Table[a265159[n - k + 1, k], {n, 9}, {k, n}]]

Formula

Conjecture 2: A(n,k) = (A055246(n)*3^k + 1)/2, so the array and A265100 are related to Cantor's ternary set.
G.f. for row n (conjectured): f(n,x) = x*(A265100(n)-(A265100(n)+1)*x)/((1-x)*(1-3*x)).