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A135871 Triangle by columns: A013610 signed and interleaved with zeros. 1
1, 0, 3, -1, 0, 9, 0, -6, 0, 27, 1, 0, -27, 0, 81, 0, 9, 0, -108, 0, 243, -1, 0, 54, 0, -405, 0, 729, 0, -12, 0, 270, 0, -1458, 0, 2187 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Row sums = even indexed Fibonacci numbers, A001906: (1, 3, 8, 21, 55,...) such that the sum of n-th row terms = F(2n). Example: sum of nonzero terms of row 4 = (- 6 + 27) = 21 = F(8).

LINKS

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

FORMULA

The triangle starts with A013610, then by columns sign (+, -, +,...) and interleave with zeros.

EXAMPLE

First few rows of the triangle are:

1;

0, 3;

-1, 0, 9;

0, -6, 0, 27;

1, 0, -27, 0, 81;

0, 9, 0, -108, 0, 243;

-1, 0, 54, 0, -405, 0, 729;

...

CROSSREFS

Cf. A013610, A001906.

Sequence in context: A078521 A194938 A299614 * A126178 A094753 A221713

Adjacent sequences:  A135868 A135869 A135870 * A135872 A135873 A135874

KEYWORD

tabl,sign

AUTHOR

Gary W. Adamson, Dec 02 2007

STATUS

approved

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Last modified October 24 02:14 EDT 2018. Contains 316541 sequences. (Running on oeis4.)