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Number of i such that d(i)<d(i-1), where Sum{d(i)*3^i: i=0,1,...,m} is base 3 representation of n.
2

%I #17 Apr 12 2022 11:33:14

%S 0,0,0,0,1,0,0,0,0,1,1,0,0,1,1,1,1,0,1,1,0,0,1,0,0,0,0,1,1,1,1,2,1,1,

%T 1,0,1,1,0,0,1,1,1,1,1,2,2,1,1,2,1,1,1,0,1,1,1,1,2,1,1,1,0,1,1,0,0,1,

%U 1,1,1,0,1,1,0,0,1,0,0,0,0,1,1,1,1,2,1,1,1,1

%N Number of i such that d(i)<d(i-1), where Sum{d(i)*3^i: i=0,1,...,m} is base 3 representation of n.

%p A037801 := proc(n)

%p a := 0 ;

%p dgs := convert(n,base,3);

%p for i from 2 to nops(dgs) do

%p if op(i,dgs)<op(i-1,dgs) then

%p a := a+1 ;

%p end if;

%p end do:

%p a ;

%p end proc: # _R. J. Mathar_, Oct 15 2015

%Y Cf. A007089, A037818.

%K nonn,base

%O 1,32

%A _Clark Kimberling_

%E Sign in name corrected by _R. J. Mathar_, Oct 15 2015