The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A115010 Array read by antidiagonals: let V(m,n) = Sum_{i=1..m, j=1..n, gcd(i,j)=1} (m+1-i)*(n+1-j), then T(m,n) = 2*m*n+m+n+2*V(m,n), for m >= 1, n >= 1. 1
 6, 13, 13, 22, 28, 22, 33, 49, 49, 33, 46, 74, 86, 74, 46, 61, 105, 131, 131, 105, 61, 78, 140, 188, 200, 188, 140, 78, 97, 181, 251, 289, 289, 251, 181, 97, 118, 226, 326, 386, 418, 386, 326, 226, 118, 141, 277, 409, 503, 559, 559, 503, 409, 277, 141, 166, 332, 502, 632, 730 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..60. Max A. Alekseyev, On the number of two-dimensional threshold functions, arXiv:math/0602511 [math.CO], 2006-2010; SIAM J. Disc. Math. 24(4), 2010, pp. 1617-1631. doi:10.1137/090750184 MAPLE V:=proc(m, n) local t1, i, j; t1:=0; for i from 1 to m do for j from 1 to n do if gcd(i, j)=1 then t1:=t1+(m+1-i)*(n+1-j); fi; od; od; t1; end; T:=(m, n)->(2*m*n+m+n+2*V(m, n)); MATHEMATICA V[m_, n_] := Sum[Boole[CoprimeQ[i, j]]*(m-i+1)*(n-j+1), {i, m}, {j, n}]; T[m_, n_] := 2*m*n + m + n + 2*V[m, n]; Table[T[m - n + 1, n], {m, 1, 12}, {n, 1, m}] // Flatten (* Jean-François Alcover, Nov 28 2017 *) CROSSREFS Cf. A114999, A114043, A115004, A115005, A115006, A115007. Sequence in context: A265740 A090324 A106623 * A244535 A066826 A031113 Adjacent sequences: A115007 A115008 A115009 * A115011 A115012 A115013 KEYWORD nonn,tabl AUTHOR N. J. A. Sloane, Feb 24 2006 STATUS approved

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.

Last modified May 27 02:41 EDT 2024. Contains 372847 sequences. (Running on oeis4.)