A062533 - OEIS

%I #24 Aug 01 2024 01:29:34

%S 1,6,8,12,20,18,20,24,24,24,42,32,40,36,36,48,44,40,60,54,64,56,72,60,

%T 72,60,48,72,88,72,96,110,80,100,84,108,72,92,120,112,84,96,120,104,

%U 132,80,156,108,120,116,120,144,160,108,96,132,168,160,132,180,140,168

%N a(n) = A000010(A014076(n)).

%H G. C. Greubel, <a href="/A062533/b062533.txt">Table of n, a(n) for n = 1..1000</a>

%t A014076 := Select[Range[1, 350, 2], PrimeOmega[#] != 1 &]; Table[ EulerPhi[A014076[[n]]], {n, 1, 50}] (* _G. C. Greubel_, Sep 17 2017 *)

%o (PARI) je=[]; forstep(n=1,301,2, if(isprime(n), n+1,je=concat(je,eulerphi(n)))); je

%o (Python)

%o from sympy import primepi, totient

%o def A062533(n):

%o     if n == 1: return 1

%o     m, k = n-1, primepi(n) + n - 1 + (n>>1)

%o     while m != k:

%o         m, k = k, primepi(k) + n - 1 + (k>>1)

%o     return totient(m) # _Chai Wah Wu_, Jul 31 2024

%Y Subset of the totients of the odds (A037225).

%Y Cf. A000010, A014076.

%K easy,nonn

%O 1,2

%A _Jason Earls_, Jul 10 2001