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A165739 The number of palindromic numbers which are the product of a number and its reversal with 2n-1 digits 0
4, 3, 8, 13, 27, 49, 99, 180, 330, 567, 957, 1546, 2479, 3865 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Every palindromic numbers which is the product of a number and its reversal has an odd number of digits

LINKS

Table of n, a(n) for n=1..14.

EXAMPLE

a(1)=4 because there are 4 numbers matching the definition with one digit: 0*0=0; 1*1=1; 2*2=4; 3*3=9;

a(2)=3 because there are 3 numbers with three digits: 11*11=121; 12*21=252; 22*22=484;

a(3)=8 because there are 8 numbers with five digits: 101*101=10201; 111*111=12321; 121*121=14641; 102*201=20502; 112*211=23632; 122*221=26962; 202*202=40804; 212*212=44944;

CROSSREFS

Cf. A158642.

Sequence in context: A316688 A309517 A105185 * A196132 A198179 A137503

Adjacent sequences:  A165736 A165737 A165738 * A165740 A165741 A165742

KEYWORD

nonn,base

AUTHOR

Floris P. van Doorn, Sep 25 2009

STATUS

approved

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Last modified August 18 04:50 EDT 2019. Contains 326072 sequences. (Running on oeis4.)