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A328708
Number of non-primitive Pythagorean triples with leg n.
3
0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 2, 0, 1, 2, 2, 0, 2, 0, 2, 2, 1, 0, 5, 1, 1, 2, 2, 0, 4, 0, 3, 2, 1, 2, 5, 0, 1, 2, 5, 0, 4, 0, 2, 5, 1, 0, 8, 1, 2, 2, 2, 0, 3, 2, 5, 2, 1, 0, 9, 0, 1, 5, 4, 2, 4, 0, 2, 2, 4, 0, 10, 0, 1, 5, 2, 2, 4, 0, 8, 3, 1, 0, 9, 2, 1, 2, 5, 0, 7, 2, 2, 2, 1, 2, 11, 0, 2, 5, 5, 0, 4
OFFSET
1,12
COMMENTS
Pythagorean triple including primitive ones and non-primitive ones. For a certain n, it may be a leg in either primitive Pythagorean triple, or non-primitive Pythagorean triple, or both.
This sequence is the count of n as leg in non-primitive Pythagorean triple.
REFERENCES
A. Beiler, Recreations in the Theory of Numbers. New York: Dover Publications, pp. 116-117, 1966.
LINKS
FORMULA
a(n) = A046079(n) - A024361(n).
EXAMPLE
n=3 as leg in only one primitive Pythagorean triple, (3,4,5); so a(3)=0.
n=6 as leg in only one non-primitive Pythagorean triple, (6,8,10); so a(6)=1.
n=8 as leg in one primitive Pythagorean triple (8,15,17) and in one non-primitive Pythagorean triple (6,8,10); so a(8)=1.
CROSSREFS
Sequence in context: A147767 A113678 A305436 * A299480 A110249 A160756
KEYWORD
nonn
AUTHOR
Rui Lin, Oct 26 2019
STATUS
approved