This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A056189 2^n - A056188(n). 1
 1, 2, 2, 8, 2, 52, 2, 128, 170, 764, 2, 2488, 2, 11624, 16928, 32768, 2, 181324, 2, 555296, 931610, 2802584, 2, 11007664, 6643782, 43955032, 44739242, 136585808, 2, 720895864, 2, 2147483648, 3250384970, 10923540812, 11517062218 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA a(n)=2^n-Sum{binomial[n, k]; k>0, GCD[n, k]=1} EXAMPLE a(n)=2 for primes; n=6, a(6)=52 because the sum of coefficients is restricted only to k=1,5 so a(6)=64-6-6. CROSSREFS Cf. A056045, A056188. Sequence in context: A095997 A274139 A283995 * A121860 A283990 A021442 Adjacent sequences:  A056186 A056187 A056188 * A056190 A056191 A056192 KEYWORD nonn AUTHOR Labos Elemer, Aug 02 2000 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 December 15 14:37 EST 2019. Contains 329999 sequences. (Running on oeis4.)