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1, -3, followed by -1's.
2

%I #42 Dec 24 2018 03:25:30

%S 1,-3,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

%T -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

%U -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1

%N 1, -3, followed by -1's.

%C 1/(n+1) is the inverse Akiyama-Tanigawa transform of A164555(n)/A027642(n).

%C For more on the Akiyama-Tanigawa transform, see Links (correction: page 7 read here A164555 instead of A027641) and A177427.

%C Here:

%C 1, -3, -1, -1, -1, -1, ...

%C 4, -4, 0, 0, 0, 0, ...

%C 8, -8, 0, 0, 0, 0, ...

%C 16, -16, 0, 0, 0, 0, ...

%C etc.

%C Other process, using signed A130534(n), different of A008275(n):

%C 1, 1/1, 1,

%C 1, 4, ( 1, -1)/1, -3,

%C 1, 4, 8, ( 2, -3, 1)/2, -1,

%C 1, 4, 8, 16, * ( 6, -11, 6, -1)/6, = -1,

%C 1, 4, 8, 16, 32, ( 24, -50, 35, -10, 1)/24, -1,

%C 1, 4, 8, 16, 32, 64, (120, -274, 225, -85, 15, -1)/120, -1,

%C etc. etc. etc.

%C Via the modified Stirling numbers of the first kind, the second triangle, Iw(n), is the inverse of Worpitzky transform A163626(n).

%C a(n) is the third sequence of a family beginning with

%C 1, 1, 1, 1, 1, 1, 1, 1, ... = A000012(n)

%C 1, 0, 0, 0, 0, 0, 0, 0, 0, ... = A000007(n)

%C 1, -3, -1, -1, -1, -1, -1, -1, -1, -1, ... .

%C A000012(n) is the inverse Akiyama-Tanigawa transform of A000007(n), with or without its second term.

%C A000007(n) is the inverse Akiyama-Tanigawa transform of A000012(n), with or without its second term.

%C a(n) is the inverse Akiyama-Tanigawa transform of 2^n omitting the second term i.e. 2.

%H Colin Barker, <a href="/A260196/b260196.txt">Table of n, a(n) for n = 0..1000</a>

%H Masanobu Kaneko, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL3/KANEKO/AT-kaneko.html">The Akiyama-Tanigawa algorithm for Bernoulli numbers</a>, Journal of Integer Sequences, 3(2000), article 00.2.9

%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).

%F Inverse Akiyama-Tanigawa transform of A151821(n).

%F From _Colin Barker_, Sep 11 2015: (Start)

%F a(n) = -1 for n>1.

%F a(n) = a(n-1) for n>2.

%F G.f.: -(2*x^2-4*x+1) / (x-1).

%F (End)

%o (PARI) first(m)=vector(m,i,i--;if(i>1,-1,if(i==0,1,if(i==1,-3)))) \\ _Anders Hellström_, Aug 28 2015

%o (PARI) Vec(-(2*x^2-4*x+1)/(x-1) + O(x^100)) \\ _Colin Barker_, Sep 11 2015

%Y Cf. A000007, A000012, A008275, A027642, A130534, A151821, A163626, A164555, A177427.

%K sign,easy

%O 0,2

%A _Paul Curtz_, Jul 19 2015