OFFSET
1,1
COMMENTS
Replacing the shorter legs with the sum and absolute difference of the shorter legs may result in an integer-sided triangle, but this is not always the case. For example, {5,12,13}->{7,13,17} and {7,13,17} are the sides of a triangle. However, {60,91,109}->{31,109,151}, but {31,109,151} are not the sides of a triangle. If the replacement results in such a triangle, then the triangle is a scalene integer triangle (A070112) with sides of prime length, and a(n) is a term of A070081.
Sequence provides x-value of solutions to the equation 2*x^2 = y^2 + z^2, with x, y and z primes. - Lamine Ngom, Apr 30 2022
EXAMPLE
13 is a term because 12 + 5 = 17 and 12 - 5 = 7.
17 is a term because 15 + 8 = 23 and 15 - 8 = 7.
37 is a term because 35 + 12 = 47 and 35 - 12 = 23.
CROSSREFS
KEYWORD
nonn
AUTHOR
Torlach Rush, May 03 2019
STATUS
approved