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A079421
Spiro-Fibonacci differences, a(n) = difference of two previous terms that are nearest when terms arranged in a spiral.
3
0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1
OFFSET
0,1
EXAMPLE
Terms are written in square boxes radiating spirally (cf. Ulam prime spiral). a(0)=0 and a(1)=1, so write 0 and then 1 to its right. a(2) goes in the box below a(1). The nearest two filled boxes contain a(0) and a(1), so a(2)=abs(a(0)-a(1))=abs(0-1)=1. a(3) goes in the box to the left of a(2). The nearest two filled boxes contain a(0) and a(2), so a(3)=abs(a(0)-a(2))=abs(0-1)=1.
CROSSREFS
Sequence in context: A109720 A022932 A334812 * A374128 A304438 A168181
KEYWORD
nonn
AUTHOR
Neil Fernandez, Jan 07 2003
STATUS
approved