The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 60th year, we have over 367,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A186320 Adjusted joint rank sequence of (f(i)) and (g(j)) with f(i) before g(j) when f(i)=g(j), where f and g are the squares and heptagonal numbers. Complement of A186321. 4
 1, 3, 5, 6, 8, 10, 11, 13, 14, 16, 18, 19, 21, 23, 24, 26, 28, 29, 31, 32, 34, 36, 37, 39, 41, 42, 44, 46, 47, 49, 50, 52, 54, 55, 57, 59, 60, 62, 63, 65, 67, 68, 70, 72, 73, 75, 77, 78, 80, 81, 83, 85, 86, 88, 90, 91, 93, 94, 96, 98, 99, 101, 103, 104, 106, 108, 109, 111, 112, 114, 116, 117, 119, 121, 122, 124, 125, 127, 129, 130, 132, 134, 135, 137, 139, 140, 142, 143, 145, 147, 148, 150, 152, 153, 155, 157, 158, 160, 161, 163 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..100. EXAMPLE First, write 1..4...9..16....25...36...49...64.. (squares) 1....7.......18....34........55.... (heptagonal) Replace each number by its rank, where ties are settled by ranking the square number before the heptagonal: a=(1,3,5,6,8,10,11,13,...)=A186320 b=(2,4,7,9,12,15,17,20,...)=A186321. MATHEMATICA (* adjusted joint ranking; general formula *) d=1/2; u=1; v=0; w=0; x=5/2; y=-3/2; z=0; h[n_]:=-y+(4x(u*n^2+v*n+w-z-d)+y^2)^(1/2); a[n_]:=n+Floor[h[n]/(2x)]; k[n_]:=-v+(4u(x*n^2+y*n+z-w+d)+v^2)^(1/2); b[n_]:=n+Floor[k[n]/(2u)]; Table[a[n], {n, 1, 100}] (* A186320 *) Table[b[n], {n, 1, 100}] (* A186321 *) CROSSREFS Cf. A186219, A186321, A186322, A186323, A000290 (squares), A000566 (heptagonal numbers). Sequence in context: A184582 A184734 A189662 * A247913 A188046 A244644 Adjacent sequences: A186317 A186318 A186319 * A186321 A186322 A186323 KEYWORD nonn AUTHOR Clark Kimberling, Feb 17 2011 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 December 7 12:41 EST 2023. Contains 367656 sequences. (Running on oeis4.)