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A108615 3-column rectangular array of near-right acute triangles. 1
4, 7, 8, 8, 9, 12, 7, 11, 13, 6, 17, 18, 11, 13, 17, 10, 15, 18, 9, 19, 21, 14, 17, 22, 13, 19, 23, 17, 21, 27, 16, 23, 28, 8, 31, 32, 11, 29, 31, 15, 26, 30, 20, 25, 32, 14, 31, 34, 19, 27, 33, 17, 34, 38, 23, 29, 37, 22, 31, 38, 13, 41, 43, 16, 41, 44, 26, 33, 42, 25, 35, 43, 10 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..72.

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 five triples:

4,7,8 (a + b + c = 19; 16 + 49 - 64 = 1)

8,9,12 (a + b + c = 29; 64 + 81 - 144 = 1)

7,11,13 (a + b + c = 31)

6,17,18 (a + b + c = 41)

11,13,17 (a + b + c = 41)

CROSSREFS

Cf. A108616.

Sequence in context: A261654 A121488 A115291 * A090383 A179620 A082390

Adjacent sequences:  A108612 A108613 A108614 * A108616 A108617 A108618

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Jun 12 2005

STATUS

approved

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Last modified February 21 21:41 EST 2018. Contains 299427 sequences. (Running on oeis4.)