This site is supported by donations to The OEIS Foundation.

 Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A068668 a(1) = 9; a(n) = smallest palindromic multiple of a(n-1). 7
 9, 99, 1881, 171171, 1882881, 306909603, 11355655311, 1033364633301, 1034397997934301, 10241574577547514201, 10231343244544544234313201, 112544775689989986577445211, 1023144555797698967975554413201 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MATHEMATICA e[1] = 9; e[n_] := e[n] = Block[{k = 2}, While[k*e[n - 1] != ToExpression[ StringReverse[ ToString[k*e[n - 1]]]], k++ ]; k*e[n - 1]]; Table[e[n], {n, 1, 13}] - Robert G. Wilson v, Apr 19 2002 CROSSREFS Cf. A068664, A068665, A068666, A068667, A070069, A068971, A068972, A068973, A068974. Sequence in context: A215243 A113395 A070068 * A035027 A196487 A262540 Adjacent sequences:  A068665 A068666 A068667 * A068669 A068670 A068671 KEYWORD base,nonn AUTHOR Amarnath Murthy, Mar 01 2002 EXTENSIONS More terms from Sascha Kurz, Mar 27 2002 Edited by N. J. A. Sloane, Apr 19 2007 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.

Last modified December 16 17:42 EST 2018. Contains 318172 sequences. (Running on oeis4.)