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A164561 Triangle with elements A120070(m,n)/A120072(m,n) read by rows, m>=2, 1<=n<m. 2
1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 16, 27, 4, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 16, 1, 4, 1, 1, 1, 9, 1, 1, 9, 1, 1, 1, 16, 1, 4, 25, 16, 1, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 27, 128, 1, 108, 1, 16, 9, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 16, 1, 4, 1, 16, 49, 4, 1, 16, 1, 4, 1, 1, 1, 27, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

2,5

LINKS

Table of n, a(n) for n=2..96.

EXAMPLE

The triangle starts in row m=2 as

1;

1, 1;

1, 4, 1;

1, 1, 1, 1;

1, 16, 27, 4, 1;

1, 1, 1, 1, 1, 1;

1, 4, 1, 16, 1, 4, 1;

MAPLE

A120070 := proc(m, n) m^2-n^2 ; end: A120072 := proc(m, n) numer(1/n^2-1/m^2) ; end:

A164561 := proc(m, n) A120070(m, n)/A120072(m, n) ; end: seq( seq(A164561(m, n), n=1..m-1), m=2..30) ; # R. J. Mathar, Aug 19 2009

CROSSREFS

Sequence in context: A185058 A204160 A184101 * A178764 A070010 A293768

Adjacent sequences:  A164558 A164559 A164560 * A164562 A164563 A164564

KEYWORD

nonn,tabl,easy

AUTHOR

Paul Curtz, Aug 16 2009

EXTENSIONS

Edited and extended by R. J. Mathar, Aug 19 2009

STATUS

approved

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Last modified October 14 12:31 EDT 2019. Contains 328006 sequences. (Running on oeis4.)