A128222 A127701 * A128174.

1, 1, 2, 3, 1, 3, 1, 4, 1, 4, 5, 1, 5, 1, 5, 1, 6, 1, 6, 1, 6, 7, 1, 7, 1, 7, 1, 7, 1, 8, 1, 8, 1, 8, 1, 8, 9, 1, 9, 1, 9, 1, 9, 1, 9, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10

Offset

1,3

Comments

Row sums = A128223: (1, 3, 7, 10, 17, 21, 31, 36, ...).

Links

Table of n, a(n) for n=1..55.

Formula

A127701 * A128174 as infinite lower triangular matrices. Odd rows: n terms of n, 1, n, ...; even rows: n terms of 1, n, 1, ...

Example

First few rows of the triangle:
  1;
  1, 2;
  3, 1, 3;
  1, 4, 1, 4;
  5, 1, 5, 1, 5;
  1, 6, 1, 6, 1, 6;
  7, 1, 7, 1, 7, 1, 7;
  ...

Mathematica

a128222[n_, k_] := If[EvenQ[n-k], n, 1]/; 1<=k<=n
a128222[r_] := Table[a128222[n, k], {n, 1, r}, {k, 1, n}]
TableForm[a128222[7]] (* triangle *)
Flatten[a128222[10]] (* data *) (* Hartmut F. W. Hoft, Mar 08 2017 *)

Crossrefs

Cf. A127701, A128174, A128223, A128222.

Sequence in context: A114899 A220906 A023678 * A057039 A369010 A260449

Adjacent sequences: A128219 A128220 A128221 * A128223 A128224 A128225

Keyword

nonn,tabl

Author

Gary W. Adamson, Feb 19 2007

Extensions

Inserted omitted values a(28) = 7 and a(29) = 1, Hartmut F. W. Hoft, Mar 08 2017

Status

approved