The OEIS is supported by the many generous donors to the OEIS Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A057097 Products of the three sides of Pythagorean triangles divided by 60. 3
 1, 8, 13, 27, 34, 64, 70, 104, 125, 203, 216, 246, 259, 272, 343, 351, 512, 560, 671, 729, 832, 918, 1000, 1092, 1113, 1331, 1547, 1624, 1625, 1728, 1890, 1968, 2002, 2072, 2176, 2197, 2744, 2808, 3164, 3212, 3333, 3375, 3927, 4096, 4250, 4459, 4480 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Note that if m appears in the sequence then k^3*m will also appear for all k and so in particular all cubes appear; the reverse is not always true (for example, 32*255*257/60 = 34952 = 2^3*4369 eventually appears, but 4369 does not). By considering the Pythagorean triangle (3k, 4k, 5k) we see that all numbers k^3 are in the sequence. - Sergey Pavlov, Mar 29 2017 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..386 FORMULA a(n) = A057096(n)/60 = A057098(n)*A057099(n)*A057100(n)/60. EXAMPLE a(1) = 3*4*5/60 = 1. MATHEMATICA (k=600000; lst={}; Do[Do[If[IntegerQ[a=Sqrt[c^2 - b^2]], If[a>=b, Break[]]; x=a b c; If[x<=k, AppendTo[lst, x]]], {b, c - 1, 4, -1}], {c, 5, 400, 1}]; Union@lst)/60 (* Vincenzo Librandi Mar 30 2017 *) CROSSREFS Cf. A000578 (cubes). Sequence in context: A205704 A337212 A093023 * A246639 A287922 A321483 Adjacent sequences: A057094 A057095 A057096 * A057098 A057099 A057100 KEYWORD nonn AUTHOR Henry Bottomley, Aug 01 2000 STATUS approved

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

Last modified September 22 21:28 EDT 2023. Contains 365531 sequences. (Running on oeis4.)