The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A331809 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A331809

a(1) = 1; a(2) = 2; thereafter a(n) is the smallest number > a(n-1) which is neither of the form 2*a(i) nor Sum_{j=1..n-1} ( b_j*a(j) ) where 0 < i < n, b_j = 1 or 0.
(history; published version)

#44 by Bruno Berselli at Wed Mar 04 03:26:02 EST 2020

STATUS

reviewed

approved

#43 by Hugo Pfoertner at Tue Mar 03 12:30:39 EST 2020

STATUS

proposed

reviewed

#42 by Hugo Pfoertner at Tue Mar 03 09:35:49 EST 2020

STATUS

editing

proposed

#41 by Hugo Pfoertner at Tue Mar 03 09:34:48 EST 2020

NAME

a(1) = 1; a(2) = 2; thereafter a(n) is the smallest number > a(n-1) which is neither in of the form 2*a(i) nor Sum_{j=1..n-1} ( b_j*a(j) ) where 0 < i < n, b_j = 1 or 0.

#40 by Michel Marcus at Tue Mar 03 09:34:39 EST 2020

EXTENSIONS

More terms, using __Rémy Sigrist__'s C++ at A331811 from Hugo Pfoertner, Jan 28 2020

STATUS

proposed

editing

#39 by Zhandos Mambetaliyev at Tue Mar 03 08:23:00 EST 2020

STATUS

editing

proposed

#38 by Zhandos Mambetaliyev at Tue Mar 03 08:22:56 EST 2020

NAME

a(1) = 1; a(2) = 2; thereafter a(n) is the smallest number > a(n-1) which is neither in the form 2*a(i) and nor Sum_{j=1..n-1} ( b_j*a(j) ) where 0 < i < n, b_j = 1 or 0.

STATUS

proposed

editing

#37 by Zhandos Mambetaliyev at Tue Mar 03 08:09:02 EST 2020

STATUS

editing

proposed

#36 by Zhandos Mambetaliyev at Tue Mar 03 08:07:36 EST 2020

DATA

3, 1, 2, 5, 9, 13, 31, 35, 92, 118, 280, 350, 866, 1102, 2668, 3368, 8240, 10444, 25420, 32156, 78464, 99352, 242128, 306440, 747272, 945976, 2306128, 2919008, 7117088, 9009040, 21964144, 27802160, 67784384, 85802464, 209191168, 264795488, 645591584, 817196512, 1992379072

OFFSET

1,12

#35 by Zhandos Mambetaliyev at Tue Mar 03 08:06:31 EST 2020

NAME

a(1) = 1; a(2) = 2; thereafter a(n) is the next smallest number after > a(n-1) which cannot be represented is neither in the form 2*a(i) and Sum_{j=1..n-1} ( b_j*a(j) ) where 0 < i < n, b_j = 1 or 0. The sequence starts: a(1) = 1; a(2) = 2. Inserting the additional term a(0) = 3 results in a so-called complete sequence after sorting.

OFFSET

0,1,1

COMMENTS

Inserting the additional term a(0) = 3 would result in a so-called complete sequence after sorting. (The sorted sequence, from smallest to largest, meets will then meet Brown's criterion.)