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CONTINUANT transform of {phi(n)}, 1, 1, 2, 2, 4, 2, .. (A002088).
1

%I #9 Aug 11 2014 22:45:17

%S 1,2,5,12,53,118,761,3162,19733,82094,840673,3444786,42178105,

%T 256513416,2094285433,17010796880,274267035513,1662613009958,

%U 30201301214757,243273022728014,2949477573950925,29738048762237264,657186550343170733,5287230451507603128

%N CONTINUANT transform of {phi(n)}, 1, 1, 2, 2, 4, 2, .. (A002088).

%H Alois P. Heinz, <a href="/A038576/b038576.txt">Table of n, a(n) for n = 1..200</a>

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

%p with(numtheory):

%p a:= proc(n) option remember; `if`(n<0, 0,

%p `if`(n=0, 1, phi(n) *a(n-1) +a(n-2)))

%p end:

%p seq(a(n), n=1..30); # _Alois P. Heinz_, Aug 17 2013

%Y Cf. A002088.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, Jun 11 2002