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 A077292 Numbers k with the property that k divides one of the concatenations (k-1)(k-2) or (k-2)(k-1). 0
 2, 3, 4, 6, 7, 17, 34, 51, 67, 167, 334, 501, 667, 1667, 3334, 5001, 6667, 14286, 16667, 33334, 50001, 66667, 166667, 333334, 500001, 666667, 1666667, 2857143, 3333334, 5000001, 6666667, 16666667, 33333334, 50000001, 66666667 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No more terms through 10^8. - Ryan Propper, Oct 11 2005 LINKS EXAMPLE 6 and 7 are terms: 6 divides 54, 7 divides 56. MATHEMATICA c[r_, s_] := ToExpression[ToString[r] <> ToString[s]]; Do[k = c[n-1, n-2]; m = c[n-2, n-1]; If[Mod[k, n] == 0 || Mod[m, n] == 0, Print[n]], {n, 2, 10^8}] (* Ryan Propper, Oct 11 2005 *) ccQ[n_]:=Module[{id1=IntegerDigits[n-1], id2=IntegerDigits[n-2]}, Divisible[ FromDigits[ Join[id1, id2]], n]||Divisible[FromDigits[Join[id2, id1]], n]]; Select[Range[2, 67000000], ccQ] (* Harvey P. Dale, Jun 18 2012 *) CROSSREFS Sequence in context: A162570 A073639 A130776 * A270475 A171249 A036413 Adjacent sequences:  A077289 A077290 A077291 * A077293 A077294 A077295 KEYWORD base,nonn AUTHOR Amarnath Murthy, Nov 03 2002 EXTENSIONS More terms from Ray G. Opao, Sep 28 2005 2 more terms from Ryan Propper, Oct 11 2005 STATUS approved

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Last modified March 22 12:39 EDT 2019. Contains 321421 sequences. (Running on oeis4.)