A106583 - OEIS

A106583

Irregular triangle read by rows generated by the morphism 1->2, 2->135, 3->2, 4->5, 5->246, 6->5 starting from a(0)=1.

1, 2, 1, 3, 5, 2, 2, 2, 4, 6, 1, 3, 5, 1, 3, 5, 1, 3, 5, 5, 5, 2, 2, 2, 4, 6, 2, 2, 2, 4, 6, 2, 2, 2, 4, 6, 2, 4, 6, 2, 4, 6, 1, 3, 5, 1, 3, 5, 1, 3, 5, 5, 5, 1, 3, 5, 1, 3, 5, 1, 3, 5, 5, 5, 1, 3, 5, 1, 3, 5, 1, 3, 5, 5, 5, 1, 3, 5, 5, 5, 1, 3, 5, 5, 5, 2, 2, 2, 4, 6, 2, 2, 2, 4, 6, 2, 2, 2, 4, 6, 2, 4, 6, 2, 4

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Alois P. Heinz, Rows n = 0..13, flattened

EXAMPLE

Triangular form:

1, 3, 5;

2, 2, 2, 4, 6;

1, 3, 5, 1, 3, 5, 1, 3, 5, 5, 5;

...

MAPLE

f:= n-> [[2], [1, 3, 5], [2], [5], [2, 4, 6], [5]][n][]:

T:= proc(n) option remember; `if`(n=0, 1, map(f, [T(n-1)])[]) end:

seq(T(n), n=0..7); # Alois P. Heinz, May 04 2026

MATHEMATICA

SubstitutionSystem[{1 -> {2}, 2 -> {1, 3, 5}, 3 -> {2}, 4 -> {5}, 5 -> {2, 4, 6}, 6 -> {5}}, {1}, 7] (* Paolo Xausa, May 12 2026 *)

CROSSREFS

Row n has length A001045(n+1).

Row sums give A290604 for n>=1.

Sequence in context: A002249 A157127 A066748 * A081450 A248408 A210880

Adjacent sequences: A106580 A106581 A106582 * A106584 A106585 A106586

KEYWORD

nonn,tabf,easy,changed

AUTHOR

Roger L. Bagula, May 09 2005

EXTENSIONS

Edited by Sean A. Irvine, May 04 2026

STATUS

approved