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A076642
Coefficient of x^a(n) in (x+1/3!)*(x+2/3!)*...*(x+n/3!) is the largest one.
1
1, 2, 2, 3, 4, 4, 4, 5, 5, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15
OFFSET
1,2
PROG
(PARI) a(n) = my(p=prod(j=1, n, x+j/6), m=vecmax(Vec(p))); for (i=0, poldegree(p), if (polcoef(p, i)==m, return(i))); \\ Michel Marcus, Feb 19 2021
(Python)
from sympy import Poly, rf
from sympy.abc import x
def A076642(n):
y = Poly(rf(6*x+1, n)).all_coeffs()[::-1]
return y.index(max(y)) # Chai Wah Wu, Mar 07 2021
CROSSREFS
Sequence in context: A097535 A060018 A089576 * A112325 A135304 A249037
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Nov 10 2002
STATUS
approved