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 A068664 a(1) = 1, a(n) = smallest palindromic multiple of a(n-1). 9
 1, 2, 4, 8, 88, 616, 6776, 88088, 616616, 232464232, 21154245112, 232696696232, 21175399357112, 21154245133154245112, 232696696464696696232, 21175399378287399357112, 63386501441764911946714410568336 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS MATHEMATICA a=1; Print[a]; For[n = 2, n <= 15, n++, {an = a; k = 2; str = ToString[k*an]; rstr = StringReverse[str]; While[str != rstr, {k = k + 1; str = ToString[k*an]; rstr = StringReverse[str]; If[k*an > 10^20, {Print["Too big"]; Abort[]}]}]; a := k*an; Print[k, " ", a]; }] CROSSREFS A068667 (from a(3) on) and this sequence (from a(6) on) coincide. Cf. A068665, A068666, A068667, A068668, A070069, A068971, A068972, A068973, A068974. Sequence in context: A237913 A076886 A046385 * A199166 A018605 A058262 Adjacent sequences:  A068661 A068662 A068663 * A068665 A068666 A068667 KEYWORD base,nonn AUTHOR Amarnath Murthy, Mar 01 2002. EXTENSIONS Extended and edited by John W. Layman, Mar 18 2002. Last two terms from David W. Wilson and Patrick De Geest, Mar 30 2002. STATUS approved

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Last modified December 16 17:25 EST 2018. Contains 318172 sequences. (Running on oeis4.)