This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A188541 a(n) = A079500(n) - 2*A079500(n-1). 2
 1, 0, 1, 1, 2, 2, 4, 5, 9, 14, 24, 40, 70, 120, 211, 371, 658, 1172, 2102, 3786, 6856, 12470, 22782, 41789, 76947, 142180, 263578, 490104, 913858, 1708386, 3201290, 6011962, 11313274, 21329276, 40282947, 76202831, 144370582, 273906268, 520359324, 989804122, 1884992934, 3593832942, 6859139352, 13104584156, 25061042050, 47971076906, 91906883496 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,5 COMMENTS Arises in studying a conjecture related to lunar divisors in base 2. LINKS Alois P. Heinz, Table of n, a(n) for n = 2..1000 D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic, arXiv:1107.1130 [math.NT], 2011. [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing] MATHEMATICA b[n_, m_] := b[n, m] = If[n == 0, 1, If[m == 0, Sum[b[n-j, j], {j, 1, n}], Sum[b[n-j, Min[n-j, m]], {j, 1, Min[n, m]}]]]; a79500[n_] := b[n, 0]; a[n_] := -a79500[n-1] + 2 a79500[n-2]; Table[a[n], {n, 2, 48}] (* Jean-François Alcover, Sep 15 2018, after Alois P. Heinz in A079500 *) CROSSREFS Cf. A079500. Sequence in context: A007147 A230380 A127968 * A037026 A116651 A135586 Adjacent sequences:  A188538 A188539 A188540 * A188542 A188543 A188544 KEYWORD nonn AUTHOR N. J. A. Sloane, Apr 03 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 22 21:43 EDT 2019. Contains 326209 sequences. (Running on oeis4.)