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A128077 A128064 * A002260. 3
1, 1, 4, 1, 2, 9, 1, 2, 3, 16, 1, 2, 3, 4, 25, 1, 2, 3, 4, 5, 36, 1, 2, 3, 4, 5, 6, 49, 1, 2, 3, 4, 5, 6, 7, 64 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Row sums = the pentagonal numbers, A000326: 1, 5, 12, 22, 35, 51,...

LINKS

Table of n, a(n) for n=1..36.

FORMULA

A128064 * A002260 as infinite lower triangular matrices. Triangle read by rows, a(1) = 1; n-th row = first (n-1) terms of (1, 2, 3...) followed by n^2.

EXAMPLE

First few rows of the triangle are:

1;

1, 4;

1, 2, 9;

1, 2, 3, 16;

1, 2, 3, 4, 25;

...

CROSSREFS

Cf. A128064, A002260, A000326, A128078.

Sequence in context: A133883 A279816 A004160 * A128078 A264922 A233528

Adjacent sequences:  A128074 A128075 A128076 * A128078 A128079 A128080

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Feb 14 2007

STATUS

approved

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Last modified March 26 20:37 EDT 2019. Contains 321534 sequences. (Running on oeis4.)