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A100723 Prime numbers whose binary representations are split into exactly seven runs. 0
149, 173, 181, 277, 293, 331, 337, 347, 349, 373, 421, 557, 587, 593, 599, 601, 613, 617, 619, 653, 659, 673, 691, 701, 709, 727, 733, 757, 809, 811, 821, 857, 859, 877, 937, 941, 1061, 1069, 1093, 1097, 1117, 1129, 1163, 1171, 1181, 1187, 1201, 1213 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The n-th prime is a member iff A100714(n)=7

LINKS

Table of n, a(n) for n=1..48.

Eric Weisstein's World of Mathematics, "Run-Length Encoding."

EXAMPLE

a(3)=181 is a member because it is the 3rd prime whose binary representation splits into exactly 7 runs. 43_10=10110101_2

MATHEMATICA

Select[Table[Prime[k], {k, 1, 50000}], Length[Split[IntegerDigits[ #, 2]]] == 7 &]

CROSSREFS

Cf. A100714, A000040.

Sequence in context: A268428 A190654 A308895 * A316589 A178127 A307472

Adjacent sequences:  A100720 A100721 A100722 * A100724 A100725 A100726

KEYWORD

base,nonn

AUTHOR

Joseph Biberstine (jrbibers(AT)indiana.edu), Dec 11 2004

STATUS

approved

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Last modified September 21 15:50 EDT 2020. Contains 337272 sequences. (Running on oeis4.)