cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A076642 Coefficient of x^a(n) in (x+1/3!)*(x+2/3!)*...*(x+n/3!) is the largest one.

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%I A076642 #17 Mar 07 2021 18:28:24
%S A076642 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 A076642 11,11,11,11,11,11,11,11,12,12,12,12,12,12,12,12,13,13,13,13,13,13,13,
%U A076642 13,13,13,14,14,14,14,14,14,14,14,14,14,14,14,15,15,15,15,15,15,15,15
%N A076642 Coefficient of x^a(n) in (x+1/3!)*(x+2/3!)*...*(x+n/3!) is the largest one.
%o A076642 (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 A076642 (Python)
%o A076642 from sympy import Poly, rf
%o A076642 from sympy.abc import x
%o A076642 def A076642(n):
%o A076642     y = Poly(rf(6*x+1,n)).all_coeffs()[::-1]
%o A076642     return y.index(max(y)) # _Chai Wah Wu_, Mar 07 2021
%Y A076642 Cf. A076620, A076634.
%K A076642 nonn
%O A076642 1,2
%A A076642 _Benoit Cloitre_, Nov 10 2002