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A037849 a(n) = Sum_{d(i) < d(i-1), i=1..m} (d(i-1) - d(i)), where Sum{d(i)*8^i: i=0,1,...,m} is the base-8 representation of n. 3

%I

%S 0,0,0,0,0,0,0,0,0,1,2,3,4,5,6,0,0,0,1,2,3,4,5,0,0,0,0,1,2,3,4,0,0,0,

%T 0,0,1,2,3,0,0,0,0,0,0,1,2,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,1,2,3,4,

%U 5,6,7,0,0,1,2,3,4,5,6,1,1,1,2,3,4,5,6,2,2,2

%N a(n) = Sum_{d(i) < d(i-1), i=1..m} (d(i-1) - d(i)), where Sum{d(i)*8^i: i=0,1,...,m} is the base-8 representation of n.

%C This is the base-8 up-variation sequence; see A297330. - _Clark Kimberling_, Jan 18 2017

%H Clark Kimberling, <a href="/A037849/b037849.txt">Table of n, a(n) for n = 1..10000</a>

%p A037849 := proc(n)

%p a := 0 ;

%p dgs := convert(n,base,8);

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

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

%p a := a-op(i,dgs)+op(i-1,dgs) ;

%p end if;

%p end do:

%p a ;

%p end proc: # _R. J. Mathar_, Oct 19 2015

%t g[n_, b_] := Differences[IntegerDigits[n, b]]; b = 8; z = 120;

%t Table[-Total[Select[g[n, b], # < 0 &]], {n, 1, z}]; (* A037858 *)

%t Table[Total[Select[g[n, b], # > 0 &]], {n, 1, z}]; (* A037849 *)

%Y Cf. A007094, A037858, A297330.

%K nonn,base

%O 1,11

%A _Clark Kimberling_

%E Definition swapped with A037858 by _R. J. Mathar_, Oct 19 2015

%E Updated by _Clark Kimberling_, Jan 19 2018

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Last modified January 23 22:36 EST 2020. Contains 331177 sequences. (Running on oeis4.)