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A178315 E.g.f.: A(x) = sqrt( Sum_{n>=0} 2^(n(n+1)/2) * x^n/n! ). 0
1, 1, 3, 23, 393, 13729, 943227, 126433847, 33245947857, 17276815511041, 17836691600303283, 36694285316980381463, 150671768689108469724633, 1235972596853128519493249569, 20265064539085026367759911941547 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..14.

EXAMPLE

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

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

PROG

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

CROSSREFS

Sequence in context: A243195 A233218 A114601 * A210910 A280654 A118195

Adjacent sequences:  A178312 A178313 A178314 * A178316 A178317 A178318

KEYWORD

nonn

AUTHOR

Paul D. Hanna, May 24 2010

STATUS

approved

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Last modified August 15 16:02 EDT 2020. Contains 336505 sequences. (Running on oeis4.)