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A247327
Triangle read by rows: T(n,k) = sum of k-th row of n X n square filled with odd numbers 1 through 2*n^2-1 reading across rows left-to-right.
1
1, 4, 12, 9, 27, 45, 16, 48, 80, 112, 25, 75, 125, 175, 225, 36, 108, 180, 252, 324, 396, 49, 147, 245, 343, 441, 539, 637, 64, 192, 320, 448, 576, 704, 832, 960, 81, 243, 405, 567, 729, 891, 1053, 1215, 1377, 100, 300, 500, 700, 900, 1100, 1300, 1500, 1700, 1900, 121, 363
OFFSET
1,2
COMMENTS
See illustration in links. Column c(k) = (2*k - 1)*n^2. Diagonal d(m) = (2*n - 2*m + 1)*n^2.
EXAMPLE
Triangle begins:
1
4 12
9 27 45
16 48 80 112
25 75 125 175 225
36 108 180 252 324 396
49 147 245 343 441 539 637
PROG
(Small Basic)
For n=1 To 20
For k=1 To n*n+(n-1)*(n-1) Step 2*n
c=0
For i=1 To n
If i=1 Then
a=k
Else
a=a+2
EndIf
c=c+a
EndFor
TextWindow.Write(c+", ")
EndFor
EndFor
(PARI) trg(nn) = {for (n=1, nn, mm = matrix(n, n, i, j, (2*j-1) + (2*n)*(i-1)); for (i=1, n, print1(sum(j=1, n, mm[i, j]), ", "); ); print(); ); } \\ Michel Marcus, Sep 15 2014
CROSSREFS
Column: c(1) = A000290, c(2) = A033428, c(3) = A033429.
Diagonal: d(1) = A015237, d(2) = A015238, d(3) = A015240.
Rows sum: A000538.
Cf. A241016.
Sequence in context: A273172 A307853 A334768 * A348419 A238581 A063608
KEYWORD
nonn,tabl
AUTHOR
Kival Ngaokrajang, Sep 13 2014
STATUS
approved