cp's OEIS Frontend

A260617 Three-dimensional array read by shells: S(i, j, k) = i + j + k; i >= 0, j >= 0, k >= 0.

%I A260617 #30 May 22 2025 10:21:43
%S A260617 0,1,1,2,1,2,2,3,2,3,2,3,4,3,4,3,4,5,2,3,4,3,4,5,4,5,6,3,4,5,3,4,5,6,
%T A260617 4,5,6,4,5,6,7,5,6,7,5,6,7,8,3,4,5,6,4,5,6,7,5,6,7,8,6,7,8,9,4,5,6,7,
%U A260617 4,5,6,7,8,5,6,7,8,5,6,7,8,9,6,7,8,9,6,7,8,9,10
%N A260617 Three-dimensional array read by shells: S(i, j, k) = i + j + k; i >= 0, j >= 0, k >= 0.
%C A260617 The triples (i,j,k) are ordered first by maximal coordinate, and then lexicographically. - _Charlie Neder_, Dec 23 2018
%H A260617 Charlie Neder, <a href="/A260617/b260617.txt">Table of n, a(n) for n = 1..1000</a>
%H A260617 Matthew Campbell, <a href="/A260617/a260617.txt">Coordinate Pattern</a>
%e A260617 S(0, 0, 0) = 0 + 0 + 0 = 0.
%e A260617 S(0, 0, 1) = 0 + 0 + 1 = 1.
%e A260617 S(0, 1, 0) = 0 + 1 + 0 = 1.
%e A260617 S(0, 1, 1) = 0 + 1 + 1 = 2.
%e A260617 S(1, 0, 0) = 1 + 0 + 0 = 1.
%e A260617 S(1, 0, 1) = 1 + 0 + 1 = 2.
%e A260617 S(1, 1, 0) = 1 + 1 + 0 = 2.
%e A260617 S(1, 1, 1) = 1 + 1 + 1 = 3.
%e A260617 S(0, 0, 2) = 0 + 0 + 2 = 2.
%e A260617 ...
%o A260617 (Python)
%o A260617 s = lambda x,y,z : x+y+z # function for 3d array
%o A260617 i = 1
%o A260617 for n in range(0,10):
%o A260617   for x in range(0,n+1):
%o A260617     for y in range(0,n+1):
%o A260617       if (x!=n and y!=n):
%o A260617         print(i, s(x,y,n))
%o A260617         i += 1
%o A260617       else:
%o A260617         for z in range(0,n+1):
%o A260617           print(i, s(x,y,z))
%o A260617           i += 1
%o A260617 # _Charlie Neder_, Dec 26 2018
%K A260617 nonn
%O A260617 1,4
%A A260617 _Matthew Campbell_, Sep 17 2015
%E A260617 Definition clarified by _Charlie Neder_, Dec 25 2018