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A182112 Number of ordered triples (w,x,y) with all terms in {-n,...,0,...,n} and (w+n)^2=x+y+w. 2
1, 4, 7, 10, 13, 16, 20, 24, 28, 32, 36, 40, 45, 50, 55, 60, 65, 70, 75, 80, 86, 92, 98, 104, 110, 116, 122, 128, 134, 140, 147, 154, 161, 168, 175, 182, 189, 196, 203, 210, 217, 224, 232, 240, 248, 256, 264, 272, 280, 288, 296, 304, 312, 320, 328, 336 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

For a guide to related sequences, see A211422.

LINKS

Table of n, a(n) for n=0..55.

MATHEMATICA

t[n_] := t[n] = Flatten[Table[(n + w)^2 - x - y - w, {w, -n, n}, {x, -n, n}, {y, -n, n}]]

c[n_] := Count[t[n], 0]

t = Table[c[n], {n, 0, 70}]  (* A182112 *)

CROSSREFS

Cf. A211422.

Sequence in context: A143456 A310682 A090852 * A090955 A310683 A134027

Adjacent sequences:  A182109 A182110 A182111 * A182113 A182114 A182115

KEYWORD

nonn

AUTHOR

Clark Kimberling, Apr 12 2012

STATUS

approved

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Last modified January 22 13:06 EST 2021. Contains 340362 sequences. (Running on oeis4.)