cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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.

This page as a plain text file.
%I A247327 #12 Feb 27 2015 23:32:55
%S A247327 1,4,12,9,27,45,16,48,80,112,25,75,125,175,225,36,108,180,252,324,396,
%T A247327 49,147,245,343,441,539,637,64,192,320,448,576,704,832,960,81,243,405,
%U A247327 567,729,891,1053,1215,1377,100,300,500,700,900,1100,1300,1500,1700,1900,121,363
%N 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.
%C A247327 See illustration in links. Column c(k) = (2*k - 1)*n^2. Diagonal d(m) = (2*n - 2*m + 1)*n^2.
%H A247327 Kival Ngaokrajang, <a href="/A247327/a247327.pdf">Illustration of initial terms</a>
%e A247327 Triangle begins:
%e A247327   1
%e A247327   4   12
%e A247327   9   27  45
%e A247327   16  48  80 112
%e A247327   25  75 125 175 225
%e A247327   36 108 180 252 324 396
%e A247327   49 147 245 343 441 539 637
%o A247327 (Small Basic)
%o A247327 For n=1 To 20
%o A247327   For k=1 To n*n+(n-1)*(n-1) Step 2*n
%o A247327     c=0
%o A247327     For i=1 To n
%o A247327       If i=1 Then
%o A247327         a=k
%o A247327       Else
%o A247327         a=a+2
%o A247327       EndIf
%o A247327       c=c+a
%o A247327     EndFor
%o A247327     TextWindow.Write(c+", ")
%o A247327   EndFor
%o A247327 EndFor
%o A247327 (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
%Y A247327 Column: c(1) = A000290, c(2) = A033428, c(3) = A033429.
%Y A247327 Diagonal: d(1) = A015237, d(2) = A015238, d(3) = A015240.
%Y A247327 Rows sum: A000538.
%Y A247327 Cf. A241016.
%K A247327 nonn,tabl
%O A247327 1,2
%A A247327 _Kival Ngaokrajang_, Sep 13 2014