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A100722
Prime numbers whose binary representations are split into exactly five runs.
0
37, 41, 43, 53, 73, 83, 89, 101, 107, 109, 137, 139, 151, 157, 163, 167, 179, 197, 211, 229, 233, 269, 281, 283, 307, 311, 313, 317, 353, 359, 367, 379, 389, 397, 401, 409, 419, 431, 433, 439, 443, 457, 461, 467, 491, 521, 523, 541, 547, 563, 569, 571, 577
OFFSET
1,1
COMMENTS
The n-th prime is a term iff A100714(n)=5.
LINKS
Eric Weisstein's World of Mathematics, Run-Length Encoding.
EXAMPLE
a(3)=43 is a term because it is the 3rd prime whose binary representation splits into exactly five runs. 43_10 = 101011_2 splits into {{1}, {0}, {1}, {0}, {1,1}}.
MATHEMATICA
Select[Table[Prime[k], {k, 1, 50000}], Length[Split[IntegerDigits[ #, 2]]] == 5 &]
CROSSREFS
Sequence in context: A071855 A137675 A161725 * A093690 A288618 A090263
KEYWORD
base,nonn
AUTHOR
Joseph Biberstine (jrbibers(AT)indiana.edu), Dec 11 2004
STATUS
approved