The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A276258 a(n) = 4*a(n-1)*a(n-2) - a(n-3), with a(1) = a(2) = a(3) = 1. 3
 1, 1, 1, 3, 11, 131, 5761, 3018753, 69564144001, 839987873581797251, 233732149587751710483796746251, 785328685279672432967483833110876164468741280003, 734226246973363127354668827312570246092792043625372932024478449584047744277761 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS Seiichi Manyama, Table of n, a(n) for n = 1..18 FORMULA a(1)=a(2)=a(3)=1; a(n)=(a(n-1)^2+a(n-2)^2+1)/a(n-3). a(n) ~ 1/4 * c^(((1+sqrt(5))/2)^n), where c = 1.41452525081158447693692520473959... . - Vaclav Kotesovec, Aug 26 2016 a(n)*a(n+1)*a(n+2) = (a(n)^2+a(n+1)^2+a(n+2)^2+1)/4. - Seiichi Manyama, Sep 04 2016 MATHEMATICA RecurrenceTable[{a[n] == 4*a[n - 1]*a[n - 2] - a[n - 3], a[1] == 1,   a[2] == 1, a[3] == 1}, a, {n, 1, 10}] (* G. C. Greubel, Aug 25 2016 *) PROG (Ruby) def A(m, n)   a = Array.new(m, 1)   ary = [1]   while ary.size < n     a = *a[1..-1], *a[1..-1].inject(:*) * (m + 1) - a[0]     ary << a[0]   end   ary end def A276258(n)   A(3, n) end CROSSREFS Cf. A001519, A064098, A276256, A276259. Sequence in context: A201611 A088075 A088076 * A284604 A072878 A112957 Adjacent sequences:  A276255 A276256 A276257 * A276259 A276260 A276261 KEYWORD nonn AUTHOR Seiichi Manyama, Aug 25 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 February 25 09:44 EST 2020. Contains 332221 sequences. (Running on oeis4.)