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Boustrophedon transform of Fibonacci numbers 1, 2, 3, 5, 8, ...
1

%I #16 Jun 12 2022 10:19:31

%S 1,3,8,22,67,229,897,4023,20512,117516,748031,5237959,40014097,

%T 331156423,2951484420,28184585550,287085799927,3106996356945,

%U 35603555478689,430652619722011,5483239453957132,73305511708044652,1026690239891085363,15033060056592047307

%N Boustrophedon transform of Fibonacci numbers 1, 2, 3, 5, 8, ...

%H C. A. Church and M. Bicknell, <a href="https://www.mathstat.dal.ca/FQ/Scanned/11-3/church.pdf">Exponential generating functions for Fibonacci identities</a>, Fibonacci Quarterly, 11(3) (1973), 275-281.

%H J. Millar, N. J. A. Sloane and N. E. Young, A new operation on sequences: the Boustrophedon transform, J. Combin. Theory, 17A (1996), 44-54 (<a href="http://neilsloane.com/doc/bous.txt">Abstract</a>, <a href="http://neilsloane.com/doc/bous.pdf">pdf</a>, <a href="http://neilsloane.com/doc/bous.ps">ps</a>).

%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>.

%F E.g.f.: (sec(x) + tan(x))*(a^2*exp(a*x) - b^2*exp(b*x))/(a - b), where a = (1 + sqrt(5))/2 and b = (1 - sqrt(5))/2. - _Petros Hadjicostas_, Feb 16 2021

%p read transforms; with(combinat, fibonacci): a := [seq(fibonacci(i),i=2..30)]: BOUS2(a);

%o (Python)

%o from itertools import accumulate, islice

%o def A092090_gen(): # generator of terms

%o blist, a, b = tuple(), 1, 2

%o while True:

%o yield (blist := tuple(accumulate(reversed(blist),initial=a)))[-1]

%o a, b = b, a+b

%o A092090_list = list(islice(A092090_gen(),40)) # _Chai Wah Wu_, Jun 12 2022

%Y Cf. A000744 (which uses BOUS2), A062122 (which uses Fibonacci numbers with an error in them), A092073.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Apr 01 2004