Svoboda | Graniru | BBC Russia | Golosameriki | Facebook
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)

Revision History for A324870

(Underlined text is an addition; strikethrough text is a deletion.)

Showing all changes.
A324870 a(n) = A324863(n) - A252464(n).
(history; published version)
#9 by Susanna Cuyler at Wed Mar 27 18:56:41 EDT 2019
STATUS

proposed

approved

#8 by Antti Karttunen at Wed Mar 27 15:52:36 EDT 2019
STATUS

editing

proposed

#7 by Antti Karttunen at Wed Mar 27 12:09:24 EDT 2019
PROG

A324861(n) = #binary(A324876(n)); \\ Needs also code from A324876.

A324863(n) = { my(m=0, w, c=0); fordiv(n, d, w=A324861(d); if(w>=m, if(w==m, c++, c=1; m=w))); (m); };

#6 by Antti Karttunen at Wed Mar 27 12:08:29 EDT 2019
PROG

A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552

A324866(n) = { my(k=A156552(n)); bitor(k, (A323243(n)-k)); }; \\ Needs also code from A323243.

A324863(n) = #binary(A324866(n));

CROSSREFS

Cf. A156552, A252464, A324863, A324866, A324871, A324872.

#5 by Antti Karttunen at Wed Mar 27 12:04:47 EDT 2019
COMMENTS

Question: Are there any other terms than 0's and 1's ? There are only 201 nonzero values among the first 10000 terms and they are all 1's ?.

LINKS

Antti Karttunen, <a href="/A324870/b324870.txt">Table of n, a(n) for n = 1..10000</a> (based on Hans Havermann's factorization of A156552)

#4 by Antti Karttunen at Thu Mar 21 10:56:10 EDT 2019
COMMENTS

Question: Are there any other terms than 0's and 1's ?

A324871 gives the numbers n where a(n) <> 0. The first such number which is not a square is 187 = 11*17.

#3 by Antti Karttunen at Thu Mar 21 09:56:28 EDT 2019
COMMENTS

A324871 gives the n where a(n) <> 0. The first such number which is not a nonsquaresquare is 187 = 11*17.

Discussion
Thu Mar 21 10:43
Antti Karttunen: Longish data section because sparse data.
#2 by Antti Karttunen at Thu Mar 21 09:55:51 EDT 2019
NAME

allocated for Antti Karttunen

a(n) = A324863(n) - A252464(n).

DATA

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1

OFFSET

1

COMMENTS

A324871 gives the n where a(n) <> 0. The first such nonsquare is 187 = 11*17.

LINKS

<a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

<a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

<a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

FORMULA

a(n) = A324863(n) - A252464(n).

PROG

(PARI)

A061395(n) = if(1==n, 0, primepi(vecmax(factor(n)[, 1])));

A252464(n) = if(1==n, 0, (bigomega(n) + A061395(n) - 1));

A324861(n) = #binary(A324876(n)); \\ Needs also code from A324876.

A324863(n) = { my(m=0, w, c=0); fordiv(n, d, w=A324861(d); if(w>=m, if(w==m, c++, c=1; m=w))); (m); };

A324870(n) = (A324863(n) - A252464(n));

KEYWORD

allocated

nonn

AUTHOR

Antti Karttunen, Mar 21 2019

STATUS

approved

editing

#1 by Antti Karttunen at Mon Mar 18 05:04:52 EDT 2019
NAME

allocated for Antti Karttunen

KEYWORD

allocated

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 11 14:15 EDT 2024. Contains 375836 sequences. (Running on oeis4.)