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 A263623 a(1)=1; thereafter, a(n) = smallest k such that the decimal concatenation [a(n-2)+1 a(n-2)+2, ... a(n-1)] divides the decimal concatenation [a(n-1)+1 a(n-1)+2 ... k]. 1
 1, 2, 4, 8, 36 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(6), if it exists, is > 10^6. - Lars Blomberg, Dec 01 2016 LINKS EXAMPLE n=3: a(3) = 4 because k=4 is the smallest number such that 2 divides the concatenation 345...k. n=4: a(4) = 8 because k=8 is the smallest number such that 34 divides the concatenation 567...k. See A002782 for the relevant concatenations. CROSSREFS Cf. A002782. Sequence in context: A094334 A138744 A243547 * A070897 A180154 A320025 Adjacent sequences: A263620 A263621 A263622 * A263624 A263625 A263626 KEYWORD nonn,base,more AUTHOR N. J. A. Sloane, Oct 23 2015 STATUS approved

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Last modified December 6 12:01 EST 2022. Contains 358634 sequences. (Running on oeis4.)