# [seqfan] Re: %F A100638 (?!)

Benoît Jubin benoit.jubin at gmail.com
Mon Dec 1 06:34:13 CET 2008

```I would write:

DEFINITION:
Successive powers of the matrix A=[1,2;3,4] written by row.
FORMULA:
a(4i+1)=(A^i)_{1,1}
a(4i+2)=(A^i)_{1,2}
a(4i+3)=(A^i)_{2,1}
a(4i+4)=(A^i)_{2,2}
Also the successive powers of the matrix A=[1,3;2,4] written by column.
OFFSET: 1
TERMS: insert at the beginning the 4 terms 1,0,0,1 corresponding to
the identity matrix A^0

Benoit

On Sun, Nov 30, 2008 at 9:05 PM, zak seidov <zakseidov at yahoo.com> wrote:
> Dear SeqFans,
> smtng's wrong with %F A100638 ...
> Anyone may wish to clarify, plz,
> thx, zak
>
>
> %I A100638
> %S A100638 1,2,3,4,7,10,15,22,37,54,81,118,199,290,435,634,1069,1558,2337,3406,
> %T A100638 5743,8370,12555,18298,30853,44966,67449,98302,165751,241570,362355,
> %U A100638 528106,890461,1297782,1946673,2837134,4783807,6972050,10458075
> %N A100638 Successive elements of powers of the matrix A=[1,2;3,4].
> %F A100638 Consider the matrix A=[1, 2;3, 4]. Then a(1)=[A_11], a(2)=[A_12], a(3)=[A_21], a(4)=[A_22],
>               a(5)=[A_11]^2, a(6)=[A_12]^2, a(7)=[A_21]^2, a(8)=[A_22]^2, a(9)=[A_11]^3,
>               a(10)=[A_12]^2, ...
> %Y A100638 Sequence in context: A078159 A129490 A018132 this_sequence A033320 A013982 A051449
> %Y A100638 Adjacent sequences: A100635 A100636 A100637 this_sequence A100639 A100640 A100641
> %K A100638 easy,nonn
> %O A100638 1,2
> %A A100638 Simone Severini (ss54(AT)york.ac.uk), Dec 04 2004
>
>
>
>
>
>
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>

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