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%I #24 Aug 23 2017 09:51:42
%S 142857,142857142857,142857142857142857,142857142857142857142857,
%T 142857142857142857142857142857,142857142857142857142857142857142857,
%U 102040816326530612244897959183673469387755,122448979591836734693877551020408163265306,142857142857142857142857142857142857142857
%N Numbers m with the property that shifting the rightmost digit of m to the left end multiplies the number by 5.
%C From _Seiichi Manyama_, Aug 22 2017: (Start)
%C For k >= 1, (10^(6*k) - 1)/7 is a term.
%C For 5 <= a <= 9 and k >= 1, a*(10^(42*k) - 1)/49 is a term. (End)
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Parasitic_number">Parasitic number</a>.
%e From _Seiichi Manyama_, Aug 22 2017: (Start)
%e b1 = 14285.
%e a(1) = b1*10 + 7,
%e 5*a(1) = 714285 = 7*10^5 + b1.
%e b7 = 10204081632653061224489795918367346938775.
%e a(7) = b7*10 + 5,
%e 5*a(7) = 510204081632653061224489795918367346938775 = 5*10^41 + b7. (End)
%Y Cf. A146088 (k=2), A146561 (k=3), A146569 (k=4), this sequence (k=5), A291215 (k=7).
%Y Cf. A092697, A097717.
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_, based on correspondence from William A. Hoffman III (whoff(AT)robill.com), Apr 10 2009
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