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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A136687 Number of palindromes in the range [0,n] inclusive. 4
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16, 16 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Partial sums of A136522. [Typo fixed by Colin Barker, Apr 26 2015]

LINKS

N. J. A. Sloane, Table of n, a(n) for n = 0..20202

FORMULA

a(n) = inv_A002113(A261423(n)), where inv_A002113 is the inverse of A002113, i.e., it yields the index of a palindrome. - M. F. Hasler, Sep 10 2018

MATHEMATICA

palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; Accumulate[ Table[ If[palQ[n], 1, 0], {n, 0, 80}]] (* Harvey P. Dale, May 11 2014 *)

PROG

(PARI) A136687(n)=inv_A002113(A261423(n)) \\ M. F. Hasler, Sep 09 2018

CROSSREFS

Cf. A002113, A136522, A137180, A261423.

Sequence in context: A051503 A179622 A285757 * A086706 A100470 A071604

Adjacent sequences:  A136684 A136685 A136686 * A136688 A136689 A136690

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Apr 21 2008

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 22 04:04 EDT 2019. Contains 322329 sequences. (Running on oeis4.)