A324051 - OEIS

%I #29 Mar 01 2019 04:26:44

%S 0,1,2,5,4,2,6,0,1,18,10,3,16,4,12,67,12,4,18,30,36,260,22,16,8,8,44,

%T 5,20,1029,30,28,164,36,28,6,256,96,44,4102,36,7,66,16,104,16391,46,

%U 12,13,32,130,8,28,51,70,480,942,65544,42,9,2724,32,66,30,84,262153,124,508,40,10,4,1048586,3320,20,188,50,52,11,78,24

%N a(n) = A106315(A156552(n)).

%C Positions of zeros, which is sequence A005940(1+A001599(n)) sorted into ascending order: 2, 9, 125, 325, 351, 4199, ..., has A324201 as its subsequence.

%H Antti Karttunen, <a href="/A324051/b324051.txt">Table of n, a(n) for n = 2..4473</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%F a(n) = A106315(A156552(n)).

%F a(n) = (A156552(n)*A324105(n)) mod A323243(n).

%o (PARI)

%o A106315(n) = (n*numdiv(n) % sigma(n));

%o A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};

%o A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));

%o A324051(n) = A106315(A156552(n));

%Y Cf. A001599, A005940, A106315, A156552, A158879, A323243, A323244, A324049, A324105, A324201.

%Y Cf. also A324057, A324187.

%K nonn

%O 2,3

%A _Antti Karttunen_, Feb 19 2019