|
%I #11 Jan 06 2017 07:44:58
%S 0,0,1,2,2,4,11,16,16,25,30,64,39,83,111,139,139,165,205,242,283,320,
%T 336,474,440,395,637,655,886,842,1019,1159,1159,1153,1327,1366,1328,
%U 1243,1487,1756,1623,2362,2394,2274,2487,2642,2907,2843,3211,3049,3736
%N a(n) = A049501(A000142(n)).
%C a(n) is the major index (1st definition) of n!.
%H Indranil Ghosh, <a href="/A280531/b280531.txt">Table of n, a(n) for n = 0..10000</a>
%e For n=4, A000142(n) = 24 and A049501(24) = 2. So a(n) = 2.
%o (Python)
%o import math
%o def M(n):
%o x=bin(int(n))[2:]
%o s=0
%o for i in range(1,len(x)):
%o if x[i-1]=="1" and x[i]=="0":
%o s+=i
%o return s
%o a=lambda n: M(math.factorial(n))
%Y Cf. A000142, A049501.
%Y Cf. A280062 (Major index (2nd definition) of n!).
%K nonn
%O 0,4
%A _Indranil Ghosh_, Jan 04 2017
|
