The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A272694 a(n) = (c(n)+f(c(n)))/2, where c() = A272693() and f(k) = sign(k)*(k mod 2). 1
 0, -1, -1, -3, -2, -2, -2, 0, 3, 1, -2, -3, -4, -3, 1, 5, 2, -3, -5, -5, -2, 3, 6, 3, -5, -11, -6, 3, 7, 5, -3, -10, -9, -2, 8, 8, 1, -8, -11, -6, 6, 10, 5, -6, -13, -9, 1, 11, 8, -3, -11, -11, -2, 9, 12, 3, -11, -17, -8, 9, 18, 9, -11, -23, -12, 9, 19, 11, -9, -22, -15, 4, 20, 14, -6, -20, -17, 2, 19, 17 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Created in an attempt to simplify the definition of A108618. LINKS N. J. A. Sloane, Table of n, a(n) for n = 0..10000 MAPLE M:=1000; a:=Array(0..M, 0); # A108618 (with different offset) b:=Array(0..M, 0); # A108619 (with different offset) c:=Array(0..M, 0); # A272693 f:=n->sign(n)*(n mod 2); a[0]:=0; b[0]:=0; c[0]:=0; for n from 1 to M do b[n]:=1+(a[n-1]+b[n-1])/2; a[n]:=1+c[n-1]+f(c[n-1])+3*f(b[n]-1); c[n]:=(a[n]-3*b[n])/2; od: [seq(a[n], n=0..M)]; [seq(b[n], n=0..M)]; [seq(c[n], n=0..M)]; [seq((c[n]+f(c[n]))/2, n=0..M)]; # A272694 CROSSREFS Cf. A108618, A108619, A272693. Sequence in context: A098054 A075801 A243160 * A292370 A116943 A328389 Adjacent sequences:  A272691 A272692 A272693 * A272695 A272696 A272697 KEYWORD sign AUTHOR N. J. A. Sloane, Jun 08 2016 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.

Last modified January 17 09:32 EST 2020. Contains 330949 sequences. (Running on oeis4.)