The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A174205 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A174205

Write natural numbers in base 2 as a stream of digits. Moving left to right, delete odd occurrences of digit 0 and 1.
(history; published version)

#18 by Peter Luschny at Mon Mar 23 17:31:34 EDT 2020

STATUS

proposed

approved

#17 by F. Chapoton at Mon Mar 23 16:49:37 EDT 2020

STATUS

editing

proposed

#16 by F. Chapoton at Mon Mar 23 16:49:29 EDT 2020

PROG

a = [0] + flatten([n.digits(base=2)[::-1] for n in IntegerRange(1, N)])

STATUS

approved

editing

Discussion

Mon Mar 23

16:49

F. Chapoton: fix syntax error in sage code

#15 by Peter Luschny at Sun Mar 08 00:05:15 EST 2020

STATUS

proposed

approved

#14 by F. Chapoton at Sat Mar 07 15:24:34 EST 2020

STATUS

editing

proposed

#13 by F. Chapoton at Sat Mar 07 15:24:25 EST 2020

PROG

def A174205(N=100):

.... a = [0] + flatten([n.digits(base=2)[::-1] for n in IntegerRange(1, 100N)]

.... for bit in 0, 1:

........ a = [d for i, d in enumerate(a) if not (d == bit and a[:i+1].count(bit) % 2 == 1)]

.... return a # D. S. McNeil, Dec 08 2010

STATUS

approved

editing

Discussion

Sat Mar 07

15:24

F. Chapoton: use space to indent sage code

#12 by Michel Marcus at Thu Mar 13 01:00:17 EDT 2014

STATUS

proposed

approved

#11 by Jon E. Schoenfield at Wed Mar 12 23:41:30 EDT 2014

STATUS

editing

proposed

#10 by Jon E. Schoenfield at Wed Mar 12 23:41:27 EDT 2014

PROG

....return a # _D. S. McNeil_, Dec 08 2010

[D. S. McNeil, Dec 8 2010]

CROSSREFS

Cf. A007088, A174203 - A174210.

STATUS

approved

editing

#9 by Charles R Greathouse IV at Fri Aug 24 10:50:03 EDT 2012

AUTHOR

_Paolo P. Lava & _ and _Giorgio Balzarotti (paoloplava(AT)gmail.com), _, Mar 15 2010

Discussion

Fri Aug 24

10:50

OEIS Server: https://oeis.org/edit/global/1825