A076642 - OEIS

%I #17 Mar 07 2021 18:28:24

%S 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,

%T 11,11,11,11,11,11,11,11,12,12,12,12,12,12,12,12,13,13,13,13,13,13,13,

%U 13,13,13,14,14,14,14,14,14,14,14,14,14,14,14,15,15,15,15,15,15,15,15

%N Coefficient of x^a(n) in (x+1/3!)*(x+2/3!)*...*(x+n/3!) is the largest one.

%o (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

%o (Python)

%o from sympy import Poly, rf

%o from sympy.abc import x

%o def A076642(n):

%o     y = Poly(rf(6*x+1,n)).all_coeffs()[::-1]

%o     return y.index(max(y)) # _Chai Wah Wu_, Mar 07 2021

%Y Cf. A076620, A076634.

%K nonn

%O 1,2

%A _Benoit Cloitre_, Nov 10 2002