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A108616 3-column rectangular array of near-right obtuse triangles. 1
4, 8, 9, 6, 18, 19, 8, 32, 33, 18, 30, 35, 10, 50, 51, 22, 46, 51, 34, 38, 51, 12, 72, 73, 28, 76, 81, 44, 68, 81, 14, 98, 99, 32, 100, 105, 68, 80, 105, 16, 128, 129, 64, 112, 129, 38, 142, 147, 60, 132, 145, 18, 162, 163, 82, 122, 147, 72, 144, 161, 42, 174, 179 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..62.

FORMULA

Row n is the n-th triple (a, b, c), in order of increasing perimeter a+b+c and increasing a, such that a < b < c and a^2 + b^2 - c^2 = -1.

EXAMPLE

First two triples:

4,8,9 (a + b + c = 21; 16 + 64 - 81 = -1)

6,18,19 (a + b + c = 43; 36 + 324 - 361 = -1)

CROSSREFS

Cf. A108615.

Sequence in context: A328906 A194623 A316251 * A200634 A154177 A010480

Adjacent sequences:  A108613 A108614 A108615 * A108617 A108618 A108619

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Jun 12 2005

STATUS

approved

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Last modified September 20 20:02 EDT 2020. Contains 337265 sequences. (Running on oeis4.)