login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A049801 Triangular array T, read by rows: T(n,k) = n mod floor(k/3), k = 3..n and n >= 3. 4

%I #30 Sep 08 2022 08:44:58

%S 0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,

%T 1,1,0,0,0,1,1,1,2,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,

%U 0,0,0,0,2,2,2,2,2,2,0,0,0,1,1,1,0,0,0,3,3,3,0

%N Triangular array T, read by rows: T(n,k) = n mod floor(k/3), k = 3..n and n >= 3.

%H G. C. Greubel, <a href="/A049801/b049801.txt">Rows n = 3..100 of triangle, flattened</a>

%e Array T(n,k) (with rows n >= 3 and columns k >= 3) begins as follows:

%e 0;

%e 0, 0;

%e 0, 0, 0;

%e 0, 0, 0, 0;

%e 0, 0, 0, 1, 1;

%e 0, 0, 0, 0, 0, 0;

%e 0, 0, 0, 1, 1, 1, 0;

%e 0, 0, 0, 0, 0, 0, 1, 1;

%e 0, 0, 0, 1, 1, 1, 2, 2, 2;

%e 0, 0, 0, 0, 0, 0, 0, 0, 0, 0;

%e 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1;

%e 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2;

%e ...

%p # To get the sequence:

%p seq(seq(n mod floor(k/3), k = 3..n), n = 3..30);

%p # To get the triangular array:

%p for n from 3 to 30 do

%p seq(n mod floor(k/3), k = 3..n);

%p end do; # _Petros Hadjicostas_, Nov 20 2019

%t Table[Mod[n, Floor[k/3]], {n,3,15}, {k,3,n}]//Flatten (* _G. C. Greubel_, Dec 09 2019 *)

%o (PARI) T(n,k) = lift(Mod(n, k\3)); \\ _G. C. Greubel_, Dec 09 2019

%o (Magma) [ n mod Floor(k/3): k in [3..n], n in [3..15]]; // _G. C. Greubel_, Dec 09 2019

%o (Sage) [[ mod(n, floor(k/3)) for k in (3..n)] for n in (3..15)] # _G. C. Greubel_, Dec 09 2019

%o (GAP) Flat(List([3..15], n-> List([3..n], k-> n mod Int(k/3) ))); # _G. C. Greubel_, Dec 09 2019

%Y Row sums are in A049799.

%Y Cf. A049797, A049798, A049800.

%K nonn,tabl

%O 3,43

%A _Clark Kimberling_

%E Name edited by and more terms from _Petros Hadjicostas_, Nov 20 2019

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 23 06:04 EDT 2024. Contains 371906 sequences. (Running on oeis4.)