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A133128 Triangle of first differences of A120070 with a leftmost column of A002522. 2
2, 5, -3, 10, -3, -5, 17, -3, -5, -7, 26, -3, -5, -7, -9, 37, -3, -5, -7, -9, -11, 50, -3, -5, -7, -9, -11, -13, 65, -3, -5, -7, -9, -11, -13, -15, 82, -3, -5, -7, -9, -11, -13, -15, -17, 101, -3, -5, -7, -9, -11, -13, -15, -17, -19, 122, -3, -5, -7, -9, -11, -13, -15, -17, -19, -21, 145, -3, -5, -7, -9, -11, -13, -15, -17, -19, -21, -23, 170, -3, -5, -7, -9, -11, -13 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

The flattened triangle is essentially the same as A141620.

LINKS

Table of n, a(n) for n=0..84.

FORMULA

T(n,0) = A002522(n+1).

T(n,m) = -2m-1, m>0 .

sum_{m=0..n} T(n,m) = 2 (row sums).

T(n,n) = -A005408(n), n>0.

EXAMPLE

The triangle starts

2;

5, -3;

10,-3,-5;

17,-3,-5,-7;

26,-3,-5,-7,-9;

MAPLE

A133128 := proc(n, m) if m>= 1 then -2*m-1 ; else (n+1)^2+1 ; fi; end: seq(seq(A133128(n, m), m=0..n), n=0..15) ; # R. J. Mathar, Nov 22 2009

CROSSREFS

Sequence in context: A332357 A305126 A044043 * A057337 A163233 A096666

Adjacent sequences:  A133125 A133126 A133127 * A133129 A133130 A133131

KEYWORD

sign,tabl,less,easy

AUTHOR

Paul Curtz, Aug 27 2008

EXTENSIONS

Edited and extended by R. J. Mathar, Nov 22 2009

STATUS

approved

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Last modified October 19 22:05 EDT 2021. Contains 348095 sequences. (Running on oeis4.)