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!)
A061858 Differences between the ordinary multiplication table A004247 and the carryless multiplication table for GF(2)[X] polynomials A048720, i.e., the effect of the carry bits in binary multiplication. 12

%I #13 Feb 14 2021 13:16:33

%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,4,0,0,0,0,0,0,0,0,0,

%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,8,0,0,8,0,0,0,0,0,0,12,0,8,0,12,0,0,0,0,

%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,8,16,8,0,0,0,0,0,0,0,0,0,0,0,24,24,0,0,0

%N Differences between the ordinary multiplication table A004247 and the carryless multiplication table for GF(2)[X] polynomials A048720, i.e., the effect of the carry bits in binary multiplication.

%F a(n) = A004247(n) - A048720(n).

%e From _Peter Munn_, Jan 28 2021: (Start)

%e The top left 12 X 12 corner of the table:

%e | 0 1 2 3 4 5 6 7 8 9 10 11

%e ------+------------------------------------------------

%e 0 | 0 0 0 0 0 0 0 0 0 0 0 0

%e 1 | 0 0 0 0 0 0 0 0 0 0 0 0

%e 2 | 0 0 0 0 0 0 0 0 0 0 0 0

%e 3 | 0 0 0 4 0 0 8 12 0 0 0 4

%e 4 | 0 0 0 0 0 0 0 0 0 0 0 0

%e 5 | 0 0 0 0 0 8 0 8 0 0 16 16

%e 6 | 0 0 0 8 0 0 16 24 0 0 0 8

%e 7 | 0 0 0 12 0 8 24 28 0 0 16 28

%e 8 | 0 0 0 0 0 0 0 0 0 0 0 0

%e 9 | 0 0 0 0 0 0 0 0 0 16 0 16

%e 10 | 0 0 0 0 0 16 0 16 0 0 32 32

%e 11 | 0 0 0 4 0 16 8 28 0 16 32 52

%e (End)

%Y "Zoomed in" variant: A061859.

%Y Rows/columns 3, 5 and 7 are given by A048728, A048729, A048730.

%Y Main diagonal divided by 4: A213673.

%Y Numbers that generate no carries when multiplied in binary by 11_2: A003714, by 101_2: A048716, by 1001_2: A115845, by 10001_2: A115847, by 100001_2: A114086.

%Y Other sequences related to the presence/absence of a carry in binary multiplication: A116361, A235034, A235040, A236378, A266195, A289726.

%K nonn,tabl,easy

%O 0,25

%A _Antti Karttunen_, May 11 2001

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 April 30 07:17 EDT 2024. Contains 372127 sequences. (Running on oeis4.)