login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A324649 Numbers n such that A318458(n) (bitwise-AND of n and sigma(n)-n) is equal to n. 7
6, 20, 28, 36, 66, 72, 88, 100, 104, 114, 132, 150, 240, 258, 264, 272, 280, 304, 354, 368, 392, 402, 464, 496, 498, 516, 550, 552, 642, 644, 680, 708, 748, 770, 774, 784, 786, 834, 836, 840, 860, 978, 1026, 1032, 1040, 1044, 1056, 1062, 1064, 1068, 1074, 1092, 1104, 1120, 1184, 1232, 1266, 1312, 1362, 1376, 1410, 1504 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Positions of zeros in A324648. Fixed points of A318458, also positions of the records in the latter.

Intersection with A324652 gives A324643.

The odd terms are: 7425, 76545, 92565, ... (A324897).

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..20000

Index entries for sequences related to binary expansion of n

Index entries for sequences related to sigma(n)

MATHEMATICA

Select[Range@ 1600, BitAnd[#, DivisorSigma[1, #] - #] == # &] (* Michael De Vlieger, Apr 21 2019, after Vincenzo Librandi at A318458 *)

PROG

(PARI) for(n=1, oo, if(bitand(n, sigma(n)-n)==n, print1(n, ", ")));

CROSSREFS

Cf. A318458, A324648, A324652.

Cf. A000396, A324643, A324897, A324898 (subsequences).

Sequence in context: A044970 A316291 A090502 * A324643 A119425 A006039

Adjacent sequences:  A324646 A324647 A324648 * A324650 A324651 A324652

KEYWORD

nonn

AUTHOR

Antti Karttunen, Mar 14 2019

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 22 04:27 EST 2020. Contains 331133 sequences. (Running on oeis4.)