%I A094926
%S A094926 0,1,1,2,3,5,8,14,23,38,63,102,168,272
%N A094926 A hexagonal spiral Fibonacci sequence.
%C A094926 Consider the following spiral:
%C A094926 ..........a(6)..a(7)..a(8)
%C A094926 .......a(5)..a(1)..a(2)..a(9)
%C A094926 ....a(14).a(4)..a(3)..a(10)
%C A094926 .......a(13).a(12).a(11)
%C A094926 Then a(1)=0, a(2)=1, a(n)=a(n-1)+Sum{a(i), a(i) is adjacent to a(n-1)};
6 terms around a(m) touch a(m).
%H A094926 N. Fernandez, <a href="http://www.borve.org/primeness/spirofib.html">
Spiro-Fibonacci numbers</a>
%e A094926 .........5..8..14
%e A094926 ........3..0..1..23
%e A094926 ...... 272. 2..1. 38
%e A094926 ........ 168.102.63
%Y A094926 Cf. A094925, A078510, A079421, A079422.
%Y A094926 Sequence in context: A000046 A131132 A004692 this_sequence A078843 A018068
A120400
%Y A094926 Adjacent sequences: A094923 A094924 A094925 this_sequence A094927 A094928
A094929
%K A094926 nonn,easy,more
%O A094926 1,4
%A A094926 Yasutoshi Kohmoto (zbi74583(AT)boat.zero.ad.jp)
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