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 A106370 Smallest b>1 such that n contains no zeros in its base b representation. 4
 2, 3, 2, 3, 3, 4, 2, 3, 4, 4, 4, 5, 3, 3, 2, 3, 3, 5, 5, 6, 4, 3, 3, 5, 3, 3, 4, 6, 4, 4, 2, 5, 5, 5, 6, 5, 4, 4, 4, 3, 3, 4, 3, 3, 4, 4, 4, 5, 3, 3, 6, 3, 3, 4, 4, 5, 4, 4, 4, 7, 4, 4, 2, 5, 6, 5, 3, 3, 5, 3, 3, 5, 5, 5, 7, 3, 3, 7, 3, 3, 5, 5, 5, 5, 4, 4, 4, 5, 4, 4, 4, 5, 4, 4, 4, 5, 5, 5, 5, 6, 4, 4, 4, 6, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n*a(n)+k) <= a(n) for 1<=k n for m < A106372(n); a(A000225(n)) = 2; a(A032924(n)) = 3 for n <> 5. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 EXAMPLE n=20: 20[binary]='101001', 20[ternary]='202', 20[base-4]='110', 20[base-5]='40', all containing at least one zero, but: 20[base-6]='32', containing no zero therefore a(20)=6. PROG (Haskell) a106370 n = f 2 n where    f b x = g x where      g 0 = b      g z = if r == 0 then f (b + 1) n else g z'            where (z', r) = divMod z b -- Reinhard Zumkeller, Apr 12 2015 CROSSREFS Cf. A106371. Cf. A000225, A032924, A106372, A119352. Sequence in context: A137467 A261461 A078627 * A128630 A273040 A319982 Adjacent sequences:  A106367 A106368 A106369 * A106371 A106372 A106373 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, May 01 2005 EXTENSIONS Typo in comment fixed by Reinhard Zumkeller, Aug 06 2010 STATUS approved

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Last modified September 20 04:40 EDT 2020. Contains 337264 sequences. (Running on oeis4.)