OFFSET
1,2
COMMENTS
Every positive integer occurs exactly once; hence, as a sequence, A185725 is a permutation of the positive integers. The square with corners T(0,0)=1 and T(n,n)=n^2 is occupied by the numbers 1,2,...,n^2.
LINKS
FORMULA
T(n,k)=(k-1)^2+2n-1 if n<=k; T(n,k)=(n-1)^2+2k if n>k.
EXAMPLE
Northwest corner:
1...2...5...10...17
3...4...7...12...19
6...8...9...14...21
11..13..15..16...23
MATHEMATICA
f[n_, k_]:=(k-1)^2+2*n-1/; n<=k;
f[n_, k_]:=(n-1)^2+2*k/; n>k;
TableForm[Table[f[n, k], {n, 1, 10}, {k, 1, 15}]]
Table[f[n-k+1, k], {n, 14}, {k, n, 1, -1}]//Flatten
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Feb 01 2011
STATUS
approved