Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A137881
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A137881 Sqrt[ A137880(n) ]. +0
4
1, 7, 15, 153, 329, 3359, 7223, 73745 (list; graph; listen)
OFFSET

1,2

COMMENT

A137880 = {1,49,225,23409,108241,11282881,52171729,5438325025,...} = Indices corresponding to the perfect squares in 17-gonal numbers A051869(n) = n(15n -13)/2.

Corresponding 17-gonal numbers k^2 are listed in A137878(n) = A051869( a(n)^2 ) = {1,17689,378225,4109707449,87870152041,954775454112481,20414169462254569,221815343046210267025,...}.

FORMULA

a(n) = Sqrt[ A137880(n) ]. A051869( a(n)^2 ) = A137878(n).

CROSSREFS

Cf. A051869 = 17-gonal numbers. Cf. A137878 = 17-gonal numbers that are the perfect squares. Cf. A137879, A137880.

Adjacent sequences: A137878 A137879 A137880 this_sequence A137882 A137883 A137884

Sequence in context: A032004 A032018 A068366 this_sequence A042725 A041096 A007541

KEYWORD

more,nonn

AUTHOR

Alexander Adamchuk (alex(AT)kolmogorov.com), Feb 19 2008

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 October 11 13:47 EDT 2008. Contains 144830 sequences.


AT&T Labs Research