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A094009
Least number k such that k! in binary representation has n consecutive ones.
1
1, 3, 7, 5, 10, 12, 33, 38, 47, 39, 67, 37, 120, 71, 189, 568, 119, 411, 952, 909, 1438, 1215, 2107, 3435, 10644, 4390, 19154, 12144, 21458, 27294, 54773, 104306, 115552, 46620, 112657, 100468
OFFSET
1,2
EXAMPLE
a(4)=5 because 5!_d = 1111000_b.
MATHEMATICA
helper[b_][a : {b_, ___}] := Length[a]; helper[b_][a_List] := 0; maxConsecutiveCount[m_List, x_] := Max[helper[x] /@ Split[m]] (* Bobby R. Treat (drbob(AT)bigfoot.com), Apr 20 2004)
a = Table[0, {30}]; Do[ b = maxConsecutiveCount[ IntegerDigits[n!, 2], 1]; If[ a[[b]] == 0, a[[b]] = n], {n, 17500}]; a
CROSSREFS
Cf. A094010.
Sequence in context: A264983 A265341 A358793 * A328185 A349772 A088514
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Apr 20 2004
EXTENSIONS
19154, 12144 and 21458 from Bobby R. Treat, Apr 21 2004
a(30) - a(36) from Robert G. Wilson v, Aug 18 2010
STATUS
approved