login

Revision History for A367745

(Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
Numbers which occur anywhere in A367795, i.e. in lists L(k) where L(1) = [1,0] and L(k+1) is obtained from L(k) by inserting their binary concatenation between elements x,y.
(history; published version)
#25 by N. J. A. Sloane at Fri Jan 19 21:36:26 EST 2024
STATUS

editing

approved

#24 by N. J. A. Sloane at Fri Jan 19 21:36:20 EST 2024
NAME

Numbers which occur anywhere in A367795, i.e. in lists L(k) where L(1) = [1,0] and L(k+1) is obtained from L(k) by inserting between elements x,y their binary concatenation between elements x,y.

STATUS

proposed

editing

#23 by Rémy Sigrist at Mon Jan 01 13:37:55 EST 2024
STATUS

editing

proposed

#22 by Rémy Sigrist at Mon Jan 01 13:35:48 EST 2024
PROG

(PARI) explore(w, p, s) = { my (ps=concat(p, s)); if (#ps <= w, if (nb++ > #vv, vv=concat(vv, vector(#vv))); vv[nb]=fromdigits(ps, 2); explore(w, p, ps); explore(w, ps, s); ); }

list_a(w) = { nb = 2; vv = [1, 0]; explore(w, [1], [0]); Set(vv[1..nb]); } \\ terms < 2^w; Rémy Sigrist, Jan 01 2024

Discussion
Mon Jan 01
13:37
Rémy Sigrist: I find this sequence really interesting; added comment + binary plot + program
#21 by Rémy Sigrist at Mon Jan 01 13:25:15 EST 2024
COMMENTS

Empirically, there are A000010(n) positive terms with n binary digits. - Rémy Sigrist, Jan 01 2024

LINKS

Rémy Sigrist, <a href="/A367745/a367745.png">Binary plot of the terms < 2^64</a>

CROSSREFS

Cf. A000010, A367795 (the triangle of L(k) lists).

STATUS

proposed

editing

#20 by Luc Rousseau at Thu Nov 30 12:17:33 EST 2023
STATUS

editing

proposed

#19 by Luc Rousseau at Thu Nov 30 12:10:27 EST 2023
NAME

Numbers which occur anywhere in A367795, i.e. in lists L(k) where L(1) = [1,0] and L(k+1) is obtained from L(k) by inserting between elements x,y their binary concatenation.

LINKS

Luc Rousseau, <a href="/A367745/a367745_1.svg">SVG illustration of the nesting of the L(k) lists for n=1..9</a>.

FORMULA

Length of L(k) = 2^(k-1) + 1 = A000051(k-1).

CROSSREFS

Cf. A000051A367795 (the triangle of L(k) lists).

Discussion
Thu Nov 30
12:11
Luc Rousseau: Moved some pieces of information to A367795 where they are more relevant.
#18 by Michael S. Branicky at Thu Nov 30 10:55:19 EST 2023
PROG

(Python)

from itertools import chain, count, islice, zip_longest

def agen(): # generator of terms

L = ["1", "0"]

for k in count(1):

yield from sorted(int(t, 2) for t in L if len(t) == k)

Lnew = [s+t for s, t in zip(L[:-1], L[1:])]

L = [t for t in chain(*zip_longest(L, Lnew)) if t is not None]

print(list(islice(agen(), 60))) # Michael S. Branicky, Nov 30 2023

Discussion
Thu Nov 30
10:55
Michael S. Branicky: just a program.
11:59
Luc Rousseau: I'm creating the A367795 entry in parallel, for the triangle version.
#17 by Luc Rousseau at Thu Nov 30 06:23:53 EST 2023
LINKS

Luc Rousseau, <a href="/A367745/a367745.svg">SVG illustration of the nesting of the L(k) lists for n=1..9</a>.

Discussion
Thu Nov 30
06:26
Luc Rousseau: SVG improved
#16 by Luc Rousseau at Thu Nov 30 06:23:25 EST 2023
LINKS

Luc Rousseau, <a href="/A367745/a367745_1.svg">SVG illustration of the nesting of the L(k) lists for n=1..9</a>.

STATUS

proposed

editing