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A057572 Number of unlabeled Hugenholz diagrams with n nodes. 1
1, 1, 12, 148, 3150, 90075, 3431015 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Hugenholz diagrams are a way of expressing terms in the quantum mechanical many-body perturbation theory.

REFERENCES

P. D. Stevenson, "Automatic Generation of Vacuum Amplitude Many-Body Perturbation Series", Int. J. Mod. Phys. C 14, 1135 (2003)

A. Szabo and N. Ostlund, Modern Quantum Chemistry, Dover Publications, New York, 1996

LINKS

Table of n, a(n) for n=1..7.

CROSSREFS

Sequence in context: A350655 A167138 A001406 * A114106 A015610 A141326

Adjacent sequences:  A057569 A057570 A057571 * A057573 A057574 A057575

KEYWORD

hard,more,nonn

AUTHOR

Paul Stevenson, Nov 28 2000

STATUS

approved

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Last modified January 20 10:33 EST 2022. Contains 350472 sequences. (Running on oeis4.)