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A051241
Number of relations with 5 arguments on n nodes.
3
2, 2147516416, 2355796086371179106111063334323891357095101187404796307182832141733986304
OFFSET
1,1
LINKS
PROG
(Python)
from itertools import product
from math import factorial, prod, lcm
from fractions import Fraction
from sympy.utilities.iterables import partitions
def A051241(n): return int(sum(Fraction(1<<sum(prod(r)//lcm(*r)*prod(p[d] for d in r) for r in product(p.keys(), repeat=5)), prod(q**p[q]*factorial(p[q]) for q in p)) for p in partitions(n))) # Chai Wah Wu, Jul 02 2024
CROSSREFS
KEYWORD
nonn,bref
STATUS
approved