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 A131537 Least power of 2 having exactly n consecutive 3's in its decimal representation. 0
 5, 25, 83, 219, 221, 2270, 11020, 18843, 192915, 271978, 743748, 1039315, 13873203, 14060685 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No more terms < 28*10^6. LINKS EXAMPLE a(3)=83 because 2^83(i.e. 9671406556917033397649408) is the smallest power of 2 to contain a run of 3 consecutive threes in its decimal form. MATHEMATICA a = ""; Do[ a = StringJoin[a, "3"]; b = StringJoin[a, "3"]; k = 1; While[ StringPosition[ ToString[2^k], a] == {} || StringPosition[ ToString[2^k], b] != {}, k++ ]; Print[k], {n, 1, 9} ] CROSSREFS Sequence in context: A062989 A122679 A147114 * A147122 A051229 A058919 Adjacent sequences:  A131534 A131535 A131536 * A131538 A131539 A131540 KEYWORD more,nonn,base AUTHOR Shyam Sunder Gupta (guptass(AT)rediffmail.com), Aug 26 2007 EXTENSIONS 3 more terms from Sean A. Irvine, Jul 19 2010 a(13)-a(14) from Lars Blomberg, Jan 24 2013 STATUS approved

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