

A298079


The number of triangles (up to congruence) with integer coordinates and perimeter in [n, n+1).


3



1, 2, 2, 6, 7, 11, 15, 26, 24, 42, 41, 66, 60, 83, 99, 126, 127, 176, 179, 219, 217, 302, 283, 374, 366, 456, 446, 551, 573, 640, 667, 808, 805, 938, 936, 1123, 1078, 1286, 1276, 1464
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OFFSET

3,2


LINKS

Peter Kagey, Table of n, a(n) for n = 3..149
Peter Kagey, Integer Triangles with perimeter less than n, Programming Puzzles & Code Golf Stack Exchange.
Peter Kagey, Haskell program for A298079.


EXAMPLE

For n = 3, all triangles with perimeter in [3, 4) are congruent to:
(0, 0), (0, 1), (1, 0) with perimeter 3.41....
For n = 4, all triangles with perimeter in [4, 5) are congruent to:
(0, 0), (0, 1), (1, 2) with perimeter 4.65..., or
(0, 0), (0, 2), (2, 0) with perimeter 4.82....
For n = 5, all triangles with perimeter in [5, 6) are congruent to:
(0, 0), (0, 2), (1, 2) with perimeter 5.23..., or
(0, 0), (1, 2), (2, 1) with perimeter 5.88....


CROSSREFS

Cf. A051518, A298121.
Sequence in context: A177852 A079811 A097869 * A295783 A060303 A099577
Adjacent sequences: A298076 A298077 A298078 * A298080 A298081 A298082


KEYWORD

nonn,more


AUTHOR

Peter Kagey, Jan 11 2018


STATUS

approved



