The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A131542 Least power of 2 having exactly n consecutive 8's in its decimal representation. 2
 3, 19, 39, 180, 316, 971, 6836, 25263, 103825, 279274, 279268, 1727604, 18053496, 8760852 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No more terms < 28*10^6. LINKS Table of n, a(n) for n=1..14. Popular Computing (Calabasas, CA), Two Tables, Vol. 1, (No. 9, Dec 1973), page PC9-16. EXAMPLE a(3)=39 because 2^39(i.e. 549755813888) is the smallest power of 2 to contain a run of 3 consecutive eights in its decimal form. MATHEMATICA a = ""; Do[ a = StringJoin[a, "8"]; b = StringJoin[a, "8"]; k = 1; While[ StringPosition[ ToString[2^k], a] == {} || StringPosition[ ToString[2^k], b] != {}, k++ ]; Print[k], {n, 1, 10} ] CROSSREFS Sequence in context: A117674 A114704 A167053 * A227878 A042371 A141644 Adjacent sequences: A131539 A131540 A131541 * A131543 A131544 A131545 KEYWORD more,nonn,base AUTHOR Shyam Sunder Gupta, Aug 26 2007 EXTENSIONS Two more terms from Sean A. Irvine, May 31 2010 a(13)-a(14) from Lars Blomberg, Jan 24 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 6 05:06 EDT 2023. Contains 363139 sequences. (Running on oeis4.)