A109929 Least palindromic multiple of concatenation n,n-1,n-2,...3,2,1.

1, 252, 180081, 855558, 335323533, 1072288822701, 1338059508331, 770589909985077, 97777777779, 98888888889, 1109887655445567889011, 739760991261414162199067937, 33436553118011488411081135563433, 4447899705293460330643925079987444, 551190490170920715517029071094091155

Offset

1,2

Comments

a(12) > 10^25. - Donovan Johnson, Mar 28 2011

Links

Table of n, a(n) for n=1..15.

Mathematica

f[n_] := Block[{k = 1, p = FromDigits[ Flatten[ IntegerDigits /@ Range[n, 1, -1]]]}, While[k p != FromDigits[ Reverse[ IntegerDigits[k p]]], k++ ]; k p]; Table[ f[n], {n, 11}] (* Robert G. Wilson v *)

Crossrefs

Cf. A109924.

Sequence in context: A248165 A289567 A179714 * A351484 A295441 A362170

Adjacent sequences: A109926 A109927 A109928 * A109930 A109931 A109932

Keyword

base,nonn

Author

Amarnath Murthy, Jul 18 2005

Extensions

Edited, corrected and extended (a(3) - a(10)) by Robert G. Wilson v, Jul 21 2005

a(11) from Donovan Johnson, Mar 28 2011

a(12)-a(15) from Giovanni Resta, Sep 23 2019

Status

approved