The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A147992 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A147992

Sequence S such that 1 is in S and if x is in S, then 4x-1 and 4x+1 are in S.
(history; published version)

#26 by Alois P. Heinz at Mon Jan 30 18:47:57 EST 2023

STATUS

editing

approved

#25 by Alois P. Heinz at Mon Jan 30 18:47:55 EST 2023

CROSSREFS

Column k=4 of A360099.

STATUS

approved

editing

#24 by Alois P. Heinz at Sun Jan 29 09:32:22 EST 2023

STATUS

editing

approved

#23 by Alois P. Heinz at Sun Jan 29 09:31:43 EST 2023

FORMULA

a(n) = 2*A032925(n-1) + 1 for n>=2. - Alois P. Heinz, Jan 29 2023

CROSSREFS

Cf. A032925.

STATUS

approved

editing

#22 by Alois P. Heinz at Tue Jun 19 15:35:42 EDT 2018

STATUS

proposed

approved

#21 by Ivan Neretin at Tue Jun 19 15:24:05 EDT 2018

STATUS

editing

proposed

#20 by Ivan Neretin at Tue Jun 19 15:23:50 EDT 2018

LINKS

Ivan Neretin, <a href="/A147992/b147992.txt">Table of n, a(n) for n = 1..10000</a>

STATUS

approved

editing

#19 by N. J. A. Sloane at Wed Jan 18 23:07:18 EST 2017

STATUS

proposed

approved

#18 by Jon E. Schoenfield at Sun Jan 15 11:05:39 EST 2017

STATUS

editing

proposed

#17 by Jon E. Schoenfield at Sun Jan 15 11:05:37 EST 2017

FORMULA

Sum_{i=2^(n-1)..2^n-1} cos(a(i)/4^(n-1)*piPi/2) = 0. - Gevorg Hmayakyan, Jan 15 2017

STATUS

proposed

editing