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!)
A098377 Left edge T(n,n) or the main diagonal of the triangle A097883. 1

%I #5 Feb 05 2014 20:18:04

%S 1,3,4,11,12,25,22,39,40,57,58,89,78,115,112,141,142,183,182,225,226,

%T 269,252,319,312,365,364,423,422,487,474,559,534,629,600,701,680,759,

%U 758,849,842,935,912,1025,1008,1117,1100,1203,1190,1311,1300,1419,1400

%N Left edge T(n,n) or the main diagonal of the triangle A097883.

%F a(n) = A097883(t) where t is a triangular number.

%t a[0, 0] = 1; a[m_, n_] := a[m, n] = Block[{p = Sort[ Flatten[ Join[ Table[ a[i, j], {i, 0, m - 1}, {j, 0, i}], Table[ a[i, j], {i, m, m}, {j, 0, n - 1}]] ]]}, k = Complement[ Range[ p[[ -1]] + 1], p][[1]]; While[ Position[p, k] != {} || If[n == 0, GCD[k, a[m - 1, 0]] != 1, If[n == m, GCD[k, a[m - 1, m - 1]] != 1, GCD[k, a[m - 1, n]] != 1 || GCD[k, a[m - 1, n - 1]] != 1]], k++ ]; k]; Table[ a[m, m], {m, 0, 52}]

%Y Cf. A097883, A098376.

%K nonn

%O 0,2

%A _Leroy Quet_ and _Robert G. Wilson v_, Sep 04 2004

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 March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)