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A128222 A127701 * A128174. 3
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 (list; table; graph; refs; listen; history; text; internal format)
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 are:

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 A260449 A135511

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

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Last modified February 22 19:56 EST 2019. Contains 320403 sequences. (Running on oeis4.)