This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A276532 a(n) = (a(n-1) * a(n-6) + a(n-2) * a(n-3) * a(n-4) * a(n-5)) / a(n-7), with a(0) = a(1) = a(2) = a(3) = a(4) = a(5) = a(6) = 1. 3
 1, 1, 1, 1, 1, 1, 1, 2, 3, 5, 11, 41, 371, 7507, 429563, 419408854, 9811194604889, 45615501062085527113, 323645006689468299915979814409, 217332607887523478570092794860281557159140687, 8092345737591989154121803868154457767563221634145658745306515944569 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,8 COMMENTS This sequence is one generalization of Dana Scott's sequence (A048736). a(n) is integer for all n. The recursion exhibits the Laurent phenomenon. See A278706 for the exponents of the denominator of the Laurent polynomial. - Michael Somos, Nov 26 2016 LINKS Seiichi Manyama, Table of n, a(n) for n = 0..26 FORMULA a(n) * a(n-7) = a(n-1) * a(n-6) + a(n-2) * a(n-3) * a(n-4) * a(n-5). a(6-n) = a(n) for all n in Z. PROG (Ruby) def A(k, n)   a = Array.new(k, 1)   ary = [1]   while ary.size < n + 1     i = a[-1] * a[1] + a[2..-2].inject(:*)     break if i % a[0] > 0     a = *a[1..-1], i / a[0]     ary << a[0]   end   ary end def A276532(n)   A(7, n) end CROSSREFS Cf. A048736, A006721, A276531, A278706. Sequence in context: A222007 A188142 A276531 * A003686 A086506 A109462 Adjacent sequences:  A276529 A276530 A276531 * A276533 A276534 A276535 KEYWORD nonn AUTHOR Seiichi Manyama, Nov 16 2016 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 July 15 16:29 EDT 2019. Contains 325049 sequences. (Running on oeis4.)