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Numbers n such that for increasing b the numbers of zeros in base b representation of n are monotonically decreasing, 1<b<n.
1

%I #4 Mar 30 2012 18:50:42

%S 1,2,4,5,6,9,11,13,19,23,43,47,59,61,97,137,139,157,277,281,283,311,

%T 313,317,421,431,619,673,821,823,827,829,947,997,1151,1663,1993,1997,

%U 2383,3359,6229,11437,11443,11447,12899,12911,12917,12919,12923,18367

%N Numbers n such that for increasing b the numbers of zeros in base b representation of n are monotonically decreasing, 1<b<n.

%C Complement of A089970.

%e m=9: '1001'[2] = '100'[3] = '21'[4] = '14'[5] = '13'[6] = '12'[7]

%e = '11'[8], 9 is a term, as number of zeros never increase.

%e m=10: 10 is not a term, as in base 5 there is 1 zero more than in

%e base 4: '1010'[2] = '101'[3] = '22'[4] = '20'[5].

%K nonn,base

%O 1,2

%A _Reinhard Zumkeller_, Nov 17 2003