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

 

Logo

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 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A100037 Positions of occurrences of the natural numbers as a second subsequence in A100035. 21
4, 9, 18, 31, 48, 69, 94, 123, 156, 193, 234, 279, 328, 381, 438, 499, 564, 633, 706, 783, 864, 949, 1038, 1131, 1228, 1329, 1434, 1543, 1656, 1773, 1894, 2019, 2148, 2281, 2418, 2559, 2704, 2853, 3006, 3163, 3324, 3489, 3658, 3831, 4008, 4189, 4374, 4563 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For n > 1, A100035(a(n)) = n and A100035(m) != n for a(n-1) <= m < a(n);

A100036(n) < a(n) < A100038(n) < A100039(n).

LINKS

Table of n, a(n) for n=1..48.

Guo-Niu Han, Enumeration of Standard Puzzles, 2011. [Cached copy]

Guo-Niu Han, Enumeration of Standard Puzzles, arXiv:2006.14070 [math.CO], 2020.

FORMULA

a(n) = 2*n^2 - n + 3 (conjectured). - Ralf Stephan, May 15 2007

EXAMPLE

First terms (10 = A, 11 = B, 12 = C) of A100035(a(n)):

...1....2........3............4................5......

1231435425165764736271879869584938291A9BA8B7A6B5A4B3A2B;

a(1) = A084849(2) = 4, A100035(4) = 1;

a(2) = A014107(2) = 9, A100035(9) = 2;

a(3) = A033537(3) = 18, A100035(18) = 3;

a(4) = A100040(4) = 31, A100035(31) = 4;

a(5) = A100041(5) = 48, A100035(48) = 5.

CROSSREFS

Cf. A014107, A033537, A084849, A100035, A100036, A100038, A100039, A100040, A100041.

Sequence in context: A301017 A008219 A008223 * A063916 A009855 A038402

Adjacent sequences: A100034 A100035 A100036 * A100038 A100039 A100040

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 31 2004

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 30 02:32 EST 2022. Contains 358431 sequences. (Running on oeis4.)