Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A113799
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A113799 Numbers n such that the n-th triangular number plus the reverse of n gives a square. +0
1
3, 36, 45, 423, 486, 558, 1377, 6690, 15540, 59460, 110694, 16867050, 443820753 (list; graph; listen)
OFFSET

1,1

EXAMPLE

T(423)+324=300^2.

MATHEMATICA

testQ[n_] := IntegerQ[Sqrt[n(n+1)/2 + FromDigits@Reverse@IntegerDigits@n]]; lst = Select[Range[10^5], testQ]

CROSSREFS

Sequence in context: A119526 A112404 A105758 this_sequence A072682 A006428 A068619

Adjacent sequences: A113796 A113797 A113798 this_sequence A113800 A113801 A113802

KEYWORD

base,nonn

AUTHOR

Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 22 2006

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