Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A098993
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A098993 Let h be the smallest value for which h, h+1, ..., h+n-1 are all lengths of hypotenuses of Pythagorean triangles. Then a(n)=h. +0
2
5, 25, 39, 50, 218, 403, 403, 403, 403, 1597, 2190, 2820, 6050, 8577, 12423, 27325, 34075, 37088, 37088, 43795, 43795, 43795, 87594, 87594, 87594, 87594, 87594, 169160, 169160, 169160, 169160, 169160, 169160, 1884817, 1884817, 1884817 (list; graph; listen)
OFFSET

1,1

COMMENT

"We can also prove (this is more difficult) that for an arbitrary natural number m there exist m Pythagorean triangles the hypotenuses of which are given by successive natural numbers, n, n+1, n+2, ..., n+m-1." Sierpinski (p. 28). No proof is given in book.

REFERENCES

W. Sierpinski, Pythagorean Triangles, Dover Publications, Mineola NY, 2003.

LINKS

D. L. Vestal, Review of "Pythagorean Triangles"(Chapter 6) by W. Sierpinski

EXAMPLE

a(4)=50 since 50, 51, 52 and 53 is the first occurrence of 4 consecutive integers which are lengths of hypotenuses of Pythagorean triangles.

MATHEMATICA

lmt = 5*10^6; hyp = {5}; Do[ mn = m^2 + n^2; hyp = Join[hyp, Table[k*mn, {k, Floor[lmt/mn]}]]; hyp = Union[hyp], {n, 2, 1150}, {m, Min[n - 1, Floor[ Sqrt[ lmt - n^2]]]}]; f[n_] := Block[{k = 1}, While[phk[[k]] + n - 1 != phk[[k + n - 1]], k++ ]; phk[[k]]]; Do[ Print[ f[n]], {n, 33} (from Robert G. Wilson v Nov 10 2004)

CROSSREFS

See A099799 for another version.

Sequence in context: A070390 A018724 A070389 this_sequence A099799 A093534 A070388

Adjacent sequences: A098990 A098991 A098992 this_sequence A098994 A098995 A098996

KEYWORD

nonn

AUTHOR

Charlie Marion (charliemath(AT)optonline.net), Nov 05 2004

EXTENSIONS

More terms from Ray Chandler (rayjchandler(AT)sbcglobal.net) and Robert G. Wilson (rgwv(AT)rgwv.com) Nov 10 2004

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified August 19 23:53 EDT 2008. Contains 142930 sequences.


AT&T Labs Research