login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A089717 Triangular numbers with palindromic indices. 0
0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 66, 253, 561, 990, 1540, 2211, 3003, 3916, 4950, 5151, 6216, 7381, 8646, 10011, 11476, 13041, 14706, 16471, 18336, 20503, 22578, 24753, 27028, 29403, 31878, 34453, 37128, 39903, 42778, 46056, 49141, 52326, 55611 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..43.

FORMULA

a(n) = A000217(A002113(n)).

CROSSREFS

Cf. A008509.

Sequence in context: A165145 A046489 A277209 * A050760 A075057 A069792

Adjacent sequences:  A089714 A089715 A089716 * A089718 A089719 A089720

KEYWORD

nonn,base

AUTHOR

Giovanni Teofilatto, Nov 24 2004

EXTENSIONS

Definition corrected by Lambert.Klasen and David Wasserman, Oct 04 2005

More terms from David Wasserman and Klaus Brockhaus, Oct 04 2005

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified February 23 03:41 EST 2018. Contains 299473 sequences. (Running on oeis4.)