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!)
 A178315 E.g.f.: A(x) = sqrt( Sum_{n>=0} 2^(n(n+1)/2) * x^n/n! ). 0

%I

%S 1,1,3,23,393,13729,943227,126433847,33245947857,17276815511041,

%T 17836691600303283,36694285316980381463,150671768689108469724633,

%U 1235972596853128519493249569,20265064539085026367759911941547

%N E.g.f.: A(x) = sqrt( Sum_{n>=0} 2^(n(n+1)/2) * x^n/n! ).

%e E.g.f.: A(x) = 1 + x + 3*x^2/2! + 23*x^3/3! + 393*x^4/4! +...

%e A(x)^2 = 1 + 2*x + 2^3*x^2/2! + 2^6*x^3/3! + 2^10*x^4/4! +...

%o (PARI) {a(n)=n!*polcoeff(sqrt(sum(m=0,n,2^(m*(m+1)/2)*x^m/m!)+x*O(x^n)),n)}

%K nonn

%O 0,3

%A _Paul D. Hanna_, May 24 2010

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 September 22 06:53 EDT 2020. Contains 337289 sequences. (Running on oeis4.)