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A309424
Sum x+y of generator pairs (x, y) {x and y coprime and not both odd} of primitive Pythagorean triangles, sorted by x and y (for same x).
2
3, 5, 5, 7, 7, 9, 7, 11, 9, 11, 13, 9, 11, 13, 15, 11, 13, 17, 11, 13, 17, 19, 13, 15, 17, 19, 21, 13, 17, 19, 23, 15, 17, 19, 21, 23, 25, 15, 17, 19, 23, 25, 27, 17, 19, 23, 29, 17, 19, 21, 23, 25, 27, 29, 31, 19, 21, 23, 25, 27, 29, 31, 33, 19, 23, 25, 29, 31, 35, 21, 23, 25, 27, 29, 31, 33, 35, 37, 21, 23, 27, 29, 31, 33, 37, 39
OFFSET
1,1
COMMENTS
This sequence is based on x and y (for same x) in increasing order, directly mapping to A094192 and A094193, while A126611 is sorted by the sum x+y.
Given any 2 of below 4 sequences, primitive Pythagorean triangles can be generated.
A094192: the bigger one in generator pairs;
A094193: the smaller one in generator pairs;
A309424: the sum of generator pairs;
A309425: the difference of generator pairs.
FORMULA
a(n) = A094192(n) + A094193(n).
CROSSREFS
KEYWORD
nonn
AUTHOR
Rui Lin, Jul 31 2019
STATUS
approved