The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A130611 Tribonacci numbers A000073 which can be the hypotenuse of a Pythagorean triple. 1
 13, 149, 274, 1705, 19513, 35890, 66012, 121415, 755476, 1389537, 4700770 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The first 2 values are hypotenuses of primitive Pythagorean triples, A000073 INTERSECTION A020882: (5^2 + 12^2 = 13^2), (51^2 + 140^2 = 149^2). The other values listed have one or more nonprimitive solution: a(6) = 35890 has 13 solutions; a(8), a(9), a(10), a(11) have 4 solutions each. LINKS FORMULA A000073 INTERSECTION A009000. {c in A000073 such that there exist integers a, b with a^2 + b^2 = c^2}. EXAMPLE a(4) = 1705 because 1023^2 + 1364^2 = 1705^2, which is a nonprimitive Pythagorean triple 341*(3,4,5). CROSSREFS Cf. A000073, A020882, A009000. Sequence in context: A132156 A324356 A210158 * A127747 A090667 A125448 Adjacent sequences:  A130608 A130609 A130610 * A130612 A130613 A130614 KEYWORD nonn AUTHOR Jonathan Vos Post, Jun 17 2007 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 26 12:36 EDT 2021. Contains 347665 sequences. (Running on oeis4.)