login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A227193 Difference of (product of runlengths of 1-bits) and (product of runlengths of 0-bits) in binary representation of n. 3
0, 0, 0, 1, -1, 0, 1, 2, -2, -1, 0, 1, 0, 1, 2, 3, -3, -2, -1, 0, -1, 0, 1, 2, -1, 0, 1, 3, 1, 2, 3, 4, -4, -3, -2, -1, -3, -1, 0, 1, -2, -1, 0, 1, 0, 1, 2, 3, -2, -1, 0, 2, 0, 1, 3, 5, 0, 1, 2, 5, 2, 3, 4, 5, -5, -4, -3, -2, -5, -2, -1, 0, -5, -3, -1, 0, -2, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,8

COMMENTS

The sequence seems to consist of palindromic subsequences centered around each (2^k)-1 and 2^k (with end points near the terms of A000975), which is easily explained by symmetric pairing of binary expansion of n and its complement.

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..10922

FORMULA

a(n) = A227349(n) - A227350(n).

MAPLE

a:= proc(n) local i, j, m, r, s; m, r, s:= n, 1, 1;

      while m>0 do

        for i from 0 while irem(m, 2, 'h')=0 do m:=h od;

        for j from 0 while irem(m, 2, 'h')=1 do m:=h od;

        r, s:= r*j, s*max(i, 1)

      od; r-s

    end:

seq(a(n), n=0..100);  # Alois P. Heinz, Jul 11 2013

MATHEMATICA

a[n_] := With[{s = Split @ IntegerDigits[n, 2]}, Times @@ Length /@ Select[ s, First[#]==1&] - Times @@ Length /@ Select[s , First[#]==0&]]; Table[ a[n], {n, 0, 100}] (* Jean-Fran├žois Alcover, Feb 28 2016 *)

PROG

(Scheme) (define (A227193 n) (- (A227349 n) (A227350 n)))

CROSSREFS

Cf. A145037, A227190.

Sequence in context: A074080 A287331 A179769 * A287397 A111407 A084440

Adjacent sequences:  A227190 A227191 A227192 * A227194 A227195 A227196

KEYWORD

sign

AUTHOR

Antti Karttunen, Jul 08 2013

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 20 11:28 EDT 2019. Contains 325180 sequences. (Running on oeis4.)