A106371 - OEIS

%I #7 Apr 12 2015 18:50:42

%S 1,2,11,11,12,12,111,22,21,22,23,22,111,112,1111,121,122,33,34,32,111,

%T 211,212,44,221,222,123,44,131,132,11111,112,113,114,55,121,211,212,

%U 213,1111,1112,222,1121,1122,231,232,233,143,1211,1212,123,1221,1222,312

%N Representation of n in base b, where b is minimal such that n contains no zeros: b = A106370(n).

%C In decimal representation feasible only for bases <= 10; A106371(11) = 360 = 2*11^2 + 10*11^1 + 8*11^0 is the first number which cannot be written zerofree with digits 1..9 in base 11. Therefore this sequence is finite with exactly 359 terms. - _Reinhard Zumkeller_, Apr 12 2015

%H Reinhard Zumkeller, <a href="/A106371/b106371.txt">Table of n, a(n) for n = 1..359</a>

%o (Haskell)

%o a106371 n = a106371_list !! (n-1)

%o a106371_list = map fromJust $ takeWhile (/= Nothing) $ map f [1..] where

%o    f n = g 2 n where

%o      g b x = h x 0 where

%o        h 0 y = if b <= 10 then Just (a004086 y) else Nothing

%o        h z y = if r == 0 then g (b + 1) n else h z' (10 * y + r)

%o                where (z', r) = divMod z b

%o -- _Reinhard Zumkeller_, Apr 12 2015

%Y Cf. A106370, A004086.

%K nonn,base,fini,full

%O 1,2

%A _Reinhard Zumkeller_, May 01 2005