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A065709
Reduced sequence related to reciprocal Pythagorean triples: 1/a(n)^2 + 1/k^2 = 1/j^2 has an integer solution (k,j) with k<a(n) and a(n) not a multiple of 20.
0
156, 255, 312, 468, 510, 609, 624, 765, 936, 1092, 1218, 1248, 1275, 1295, 1404, 1530, 1716, 1785, 1827, 1872, 2028, 2184, 2295, 2385, 2436, 2496, 2550, 2590, 2652, 2805, 2808, 2964, 3045, 3276, 3315, 3432, 3570, 3588, 3654, 3744, 3825, 3885, 4015, 4056, 4095
OFFSET
1,1
EXAMPLE
a(10)=1218: 1/a(10)^2 + 1/1160^2 = 1/840^2
CROSSREFS
A065607 (includes multiples of 20)
Sequence in context: A295221 A052477 A166397 * A037983 A298909 A366172
KEYWORD
nonn
AUTHOR
Len Smiley, Dec 04 2001
EXTENSIONS
Offset corrected and more terms from Sean A. Irvine, Sep 09 2023
STATUS
approved