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 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #27 Jun 16 2024 16:46:25
%S 4,3,3,1,2,9,2,4,2,4,4,9,9,7,1,3,4,6,5,8,3,8,9,4,1,4,9,1,0,4,2,3,3,8,
%T 0,8,1,1,3,8,5,6,1,5,4,6,0,2,6,7,8,2,2,9,7,2,8,7,4,9,9,5,5,7,4,8,5,7,
%U 5,2,1,7,4,7,9,4,1,7,3,7,6,1,4,6,8,8,2,7,5,2,1,3,3,9,2,4,4,1,5,3,3,9,4,5,1
%N Decimal expansion of the constant x satisfying x! = Gamma(x+1) = 40.
%C Solutions were provided by Bob Hanlon and Peter Pein.
%e 4.331292424499713465838941491042338081138561546026782297287499557485752...
%p read("transforms3") ; Digits := 120 ; x := 4.0 ; for l from 1 to 10 do x := x-(1-40/GAMMA(x+1))/Psi(x+1) ; x := evalf(x) ; end do; CONSTTOLIST(x) ; # _R. J. Mathar_, Mar 23 2010
%t FindRoot[(x + 1)! == 40, {x, 4, 5}, WorkingPrecision -> 50]( * Bob Hanlon (hanlonr(AT)cox.net) and Peter Pein, edited by _M. F. Hasler_, Jun 16 2024 *)
%o (PARI) A129624_first(N=99, t=40, L=log(t)*.55)=localprec(N+5); digits(solve(x=L+1.5,L+2.5,gamma(x+1)-t)\10^-N) \\ _M. F. Hasler_, Jun 13 2024
%Y Similar for x! = n: A319275 (n=3), A319276 (n=4), A319277 (n=5).
%K nonn,cons
%O 1,1
%A _Roger L. Bagula_, May 30 2007
%E More digits from _R. J. Mathar_, Mar 23 2010