Monday, 24 November 2014

Yellow Submarine

Free, one-sided, and fixed polyknights
There are three common ways of distinguishing polyominoes and polyknights
free polyknights are distinct when none is a rigid transformation ( translation, rotation, reflection or glide reflection ) of another ( pieces that can be picked up and flipped over ).  one-sided polyknights are distinct when none is a translation or rotation of another  ( pieces that cannot be flipped over ).
fixed polyknights are distinct when none is a translation of another  ( pieces that can be neither flipped nor rotated ).  Yellow submarine shows polyknights of various types with 2 cells.


Chessboard Polyominoes

Chessboard Polyominoes with n squares. ( A001933 )
2, 1, 4, 7, ...


Wednesday, 5 November 2014

Sunday, 26 October 2014

the hollow and the silk

parity groupings in two dimensions and the array is shown in expanded view


Monday, 6 October 2014

triples of perception

when looking at a sequence of symbols 3 numbers are perceptually present
00          we see 2 symbols and 1 adjacent pair and count 2 symbols from the adjacent pair
000        we see 3 symbols and 2 adjacent pairs and count 4 symbols from the adjacent pairs
0000      we see 4 symbols and 3 adjacent pairs and count 6 symbols from the adjacent pairs
00000    we see 5 symbols and 4 adjacent pairs and count 8 symbols from the adjacent pairs
000000  we see 6 symbols and 5 adjacent pairs and count 10 symbols from the adjacent pairs
0-n0s-0  we see n symbols and n-1 adjacent pairs and count 2(n-1) symbols from the adjacent pairs
so with a worked out example
how many numbers do we naturally see in  oooo  ??
oooo            4
oo oo oo      3
oooooo        6
or the numbers 12 and 13 used in musical scales
12 notes from C to B
13 notes from C to C
12 semitones from C to C
and from the triples of perception idea we see these numbers
12, 11, 22
13, 12, 24
exploring adjacency with math art
the simplest example of emergence one could possibly think of is
the zig zag motion eyes do when counting adjacent pairs in a sequence
two tw wo
spooky
sp po oo ok ky
sppooookky
sp pp po oo oo oo ok kk ky
 
 

Friday, 29 August 2014

[[{{ institutions of higher learning }}]] and {{ LPFs & GPFs together }}

add 1, multiply by 1, add 2, multiply by 2, etcetera
prime powers in mauve, LPFs in orange with bonus pink squares to reach the GPFs

Wednesday, 27 August 2014

An angel at my picnic

The ruler function: 2^a(n) divides 2n. Or, a(n) = 2-adic valuation of 2n.  ( OEIS A001511 )
1, 2, 1, 3, 1, 2, 1, 4, 1, 2, 1, 3, 1, 2, 1, 5, 1, 2, 1, 3, 1, 2, 1, 4, 1, 2, 1, 3, 1, 2, 1, 6, 1, 2, 1, 3, 1, 2, 1, 4, 1, 2, 1, 3, 1, 2, 1, 5, 1, 2, 1, 3, ...
Quarter-squares: floor(n/2)*ceiling(n/2). Equivalently, floor(n^2/4).   ( OEIS A002620 )
0, 0, 1, 2, 4, 6, 9, 12, 16, 20, 25, 30, 36, 42, 49, 56, 64, 72, 81, 90, 100, 110, 121, 132, 144, 156, 169, 182, 196, 210, 225, 240, 256, ...
Some examples :
for n=2, 3, 4, 5, 6, 7, 8, 9, 10  have  1*1,  1*2,  2*2,  2*3,  3*3,  3*4,  4*4,  4*5  and  5*5

Thursday, 31 July 2014

the weaver bird

Weaver birds, also known as weaver finches, get their name because of their elaborately woven nests
(the most elaborate of any birds'), though some are notable for their selective parasitic nesting habits. The nests vary in size, shape, material used, and construction techniques from species to species.
(Source: Wikipedia)
Yay, for all the wonderful bird life in nature !

Monday, 21 July 2014

transport Egyptian fractions { keep on truckin' }


5/12 = 1/4 + 1/10 + 1/15 = 1/5 + 1/6 + 1/20
Lcm( 12, 4, 10, 15, 5, 6, 20 ) = 60

25/60 = 15/60 + 6/60 + 4/60 = 12/60 + 10/60 + 3/60

60 is the smallest number with 6 representations as a sum of 2 primes:

60 = 7+53 = 13+47 = 17+43 = 19+41 = 23+37 = 29+31