Search: id:A000699 Results 1-1 of 1 results found. %I A000699 M3618 N1468 %S A000699 1,1,4,27,248,2830,38232,593859,10401712,202601898,4342263000, %T A000699 101551822350,2573779506192,70282204726396,2057490936366320, %U A000699 64291032462761955,2136017303903513184,75197869250518812754 %N A000699 Number of irreducible diagrams with 2n nodes. %C A000699 Perturbation expansion in quantum field theory: spinor case in 4 spacetime dimensions. %D A000699 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A000699 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A000699 D. J. Broadhurst and D. Kreimer, Combinatoric explosion of renormalization tamed by Hopf algebra: 30-loop Pad-Borel resummation. Phys. Lett. B 475 (2000), 63-70. %D A000699 M. Klazar, Non-P-recursiveness of numbers of matchings or linear chord diagrams with many crossings, Advances in Appl. Math., Vol. 30 (2003), pp. 126-136. %D A000699 M. Klazar, Counting even and odd partitions, Amer. Math. Monthly, 110 (No. 6, 2003), 527-532. %D A000699 Nijenhuis, Albert and Wilf, Herbert S., The enumeration of connected graphs and linked diagrams, J. Combin. Theory Ser. A 27 (1979), no. 3, 356-359. %D A000699 R. R. Stein, On a class of linked diagrams, I. Enumeration, J. Combin. Theory, A 24 (1978), 357-366. %D A000699 R. R. Stein and C. J. Everett, On a class of linked diagrams, II. Asymptotics, Discrete Math., 21 (1978), 309-318. %D A000699 J. Touchard, Sur un proble`me de configurations et sur les fractions continues, Canad. J. Math., 4 (1952), 2-25. %H A000699 T. D. Noe, Table of n, a(n) for n=1..100 %H A000699 D. J. Broadhurst and D. Kreimer, Combinatoric explosion of renormalization ... %H A000699 P. Flajolet and M. Noy, Analytic Combinatorics of Chord Diagrams %F A000699 a(n) = (n-1)*Sum_{i=1..n-1} a(i)*a(n-i). %e A000699 a(31)=627625976637472254550352492162870816129760 was computed using Kreimer's Hopf algebra of rooted trees. It subsumes 2.6*10^21 terms in quantum field theory. %Y A000699 Cf. A004300, A051862. %Y A000699 Sequence in context: A161120 A121063 A051863 this_sequence A138423 A158836 A086783 %Y A000699 Adjacent sequences: A000696 A000697 A000698 this_sequence A000700 A000701 A000702 %K A000699 nonn,easy,nice %O A000699 1,3 %A A000699 N. J. A. Sloane (njas(AT)research.att.com). %E A000699 More terms from David Broadhurst (D.Broadhurst(AT)open.ac.uk), Dec 14 1999 Search completed in 0.002 seconds