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A300166 Numbers of the form m^2 + 1 that can be expressed in more than one way as j^2 + k^2 with j > k > 1 and gcd(j,k) = 1. 5
2210, 5185, 5330, 6890, 9605, 12545, 14885, 15130, 16385, 17425, 17690, 19045, 20165, 21905, 24650, 26245, 29585, 29930, 30277, 31330, 33490, 34970, 36482, 36865, 40001, 41210, 43265, 44945, 45370, 46657, 47090, 51985, 54290, 56170, 58565, 63505 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The sequence differs from A299708 by the gcd condition, which excludes representations like 325 = 18^2 + 1^2 = 15^2 + 10^2, 1025 = 32^2 + 1 = 25^2 + 20^2, 1445 = 38^2 + 1 = 34^2 + 17^2.
LINKS
EXAMPLE
a(1) = 2210 because its 3 representations satisfy the conditions j > k > 1 and gcd(j,k) = 1: 2210 = 47^2 + 1 = 43^2 + 19^2 = 41^2 + 23^2 = 37^2 + 29^2.
CROSSREFS
Sequence in context: A178458 A248712 A226562 * A031772 A305880 A031545
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Feb 27 2018
STATUS
approved

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Last modified May 13 17:28 EDT 2024. Contains 372522 sequences. (Running on oeis4.)