The On-Line Encyclopedia of Integer Sequences (OEIS)

A158948 revision #8

A158948

Triangle read by rows, left border = natural numbers repeated (1, 1, 2, 2, 3, 3, ...); all other columns = (1, 0, 1, 0, 1, 0, ...).

1, 1, 1, 2, 0, 1, 2, 1, 0, 1, 3, 0, 1, 0, 1, 3, 1, 0, 1, 0, 1, 4, 0, 1, 0, 1, 0, 1, 4, 1, 0, 1, 0, 1, 0, 1, 5, 0, 1, 0, 1, 0, 1, 0, 1, 5, 1, 0, 1, 0, 1, 0, 1, 0, 1

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OFFSET

1,4

COMMENTS

Row sums = n. Eigensequence of the triangle = nonzero terms of A000071: (1, 2, 4, 7, 12, 20, ...) = ((F3 - 1), (F4 - 1), (F5 - 1), ...).

LINKS

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

FORMULA

Triangle by rows, left border = natural numbers repeated (1, 1, 2, 2, 3, 3, ...); all other columns = (1, 0, 1, 0, 1, 0, ...).

EXAMPLE

First few rows of the triangle:

1, 1;

2, 0, 1;

2, 1, 0, 1;

3, 0, 1, 0, 1;

3, 1, 0, 1, 0, 1;

4, 0, 1, 0, 1, 0, 1;

4, 1, 0, 1, 0, 1, 0, 1;

5, 0, 1, 0, 1, 0, 1, 0, 1;

5, 1, 0, 1, 0, 1, 0, 1, 0, 1;

6, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1;

6, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1;

7, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1;

...

CROSSREFS

Cf. A000071.

Sequence in context: A293386 A322522 A168121 * A140224 A075993 A117170

Adjacent sequences: A158945 A158946 A158947 * A158949 A158950 A158951

KEYWORD

nonn,tabf

AUTHOR

Gary W. Adamson, Mar 31 2009

STATUS

approved