The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A246601 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A246601

Sum of divisors d of n with property that the binary representation of d can be obtained from the binary representation of n by changing any number of 1's to 0's.
(history; published version)

#27 by Michael De Vlieger at Fri Dec 16 09:00:14 EST 2022

STATUS

reviewed

approved

#26 by Michel Marcus at Fri Dec 16 01:50:32 EST 2022

STATUS

proposed

reviewed

#25 by Amiram Eldar at Thu Dec 15 18:01:15 EST 2022

STATUS

editing

proposed

#24 by Amiram Eldar at Thu Dec 15 18:00:55 EST 2022

COMMENTS

Also, Equivalently, the sum of the divisors d of n such that the bitwise AND of n and d is equal to d. - Amiram Eldar, Dec 15 2022

STATUS

proposed

editing

#23 by Amiram Eldar at Thu Dec 15 15:44:48 EST 2022

STATUS

editing

proposed

#22 by Amiram Eldar at Thu Dec 15 15:21:06 EST 2022

FORMULA

a(2*n) = 2*a(n), and therefore a(m*2^k) = 2^k*a(m) for m odd and k>=0.

a(2^n-1) = sigma(2^n-1) = A075708(n). (End)

CROSSREFS

Cf. A000005, A000203, A075708, A246600.

#21 by Amiram Eldar at Thu Dec 15 14:56:36 EST 2022

COMMENTS

Also, the sum of the divisors d of n such that the bitwise AND of n and d is equal to d. - Amiram Eldar, Dec 15 2022

#20 by Amiram Eldar at Thu Dec 15 14:52:38 EST 2022

FORMULA

From Amiram Eldar, Dec 15 2022: (Start)

a(2*n) = 2*a(n), and therefore a(m*2^k) = 2^k*a(m) for m odd and k>=0.

a(2^n-1) = sigma(2^n-1). (End)

STATUS

approved

editing

#19 by N. J. A. Sloane at Thu Dec 03 04:31:19 EST 2015

STATUS

proposed

approved

#18 by Jean-François Alcover at Wed Dec 02 14:15:57 EST 2015

STATUS

editing

proposed