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A247647 Binary numbers that begin and end with 1 and do not contain two adjacent zeros. 6
1, 11, 101, 111, 1011, 1101, 1111, 10101, 10111, 11011, 11101, 11111, 101011, 101101, 101111, 110101, 110111, 111011, 111101, 111111, 1010101, 1010111, 1011011, 1011101, 1011111, 1101011, 1101101, 1101111, 1110101, 1110111, 1111011, 1111101, 1111111, 10101011, 10101101, 10101111, 10110101, 10110111, 10111011, 10111101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = A007088(A247648(n)).

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..1000

PROG

(Python)

A247647_list = [int(bin(n)[2:]) for n in range(1, 10**5) if n % 2 and not '00' in bin(n)]

# Chai Wah Wu, Sep 25 2014

(Haskell)

a247647 = a007088 . a247648  -- Reinhard Zumkeller, Sep 25 2014

CROSSREFS

See A247648 for the decimal equivalents.

Cf. A007088, A247649, A253085.

Sequence in context: A264406 A057148 A076289 * A240602 A117697 A305395

Adjacent sequences:  A247644 A247645 A247646 * A247648 A247649 A247650

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Sep 25 2014

STATUS

approved

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Last modified September 20 06:51 EDT 2020. Contains 337264 sequences. (Running on oeis4.)