This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A193375 E.g.f.: A(x) = exp( Sum_{n>=1} x^(n*(n+1)/2) ). 2
 1, 1, 1, 7, 25, 61, 1201, 7771, 30577, 514585, 8089921, 63701551, 832599241, 14055894997, 137066892145, 3084240161731, 70859008063201, 849408115312561, 15997591979202817, 358582896987674455, 6017079190150763641, 209473179919282488301 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS EXAMPLE E.g.f.: A(x) = 1 + x + x^2/2! + 7*x^3/3! + 25*x^4/4! + 61*x^5/5! +... where log(A(x)) = x + x^3 + x^6 + x^10 + x^15 + x^21 +... PROG (PARI) {a(n)=n!*polcoeff(exp(sum(m=1, sqrtint(2*n+1), x^(m*(m+1)/2)+x*O(x^n))), n)} CROSSREFS Cf. A193374. Sequence in context: A321165 A118395 A118396 * A185787 A299273 A001845 Adjacent sequences:  A193372 A193373 A193374 * A193376 A193377 A193378 KEYWORD nonn AUTHOR Paul D. Hanna, Jul 24 2011 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 October 13 19:48 EDT 2019. Contains 327981 sequences. (Running on oeis4.)