A073871 - OEIS

%I #10 Jan 19 2025 09:26:37

%S 4,3,3,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,1,2,2,2,1,2,1,2,2,1,2,2,1,2,

%T 1,2,2,2,1,2,2,1,2,2,1,2,2,2,1,1,1,2,2,1,1,2,1,2,2,1,2,2,1,2,1,1,2,2,

%U 1,1,2,2,2,2,1,2,1,1,2,2,1,2,2,1,1,2,1,2,2,1,1,2,1,2,1,2,2,1,1,1,2,1,2,2,1

%N A073870 divided by n.

%H Antti Karttunen, <a href="/A073871/b073871.txt">Table of n, a(n) for n = 1..20000</a>

%F a(1)=4, a(2) = a(3) = 3. For n > 3, if the odd part of n is 1, 9, or a prime, a(n) = 2, otherwise a(n) = 1. - _Franklin T. Adams-Watters_, May 12 2006

%o (PARI) A073871(n) = if(n<=3, 3+(1==n), my(op=n>>valuation(n,2)); if(1==op || 9==op || isprime(op), 2, 1)); \\ _Antti Karttunen_, Jan 19 2025

%Y Cf. A073870.

%Y Cf. A000265.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Aug 16 2002

%E Corrected and extended by _Franklin T. Adams-Watters_, May 12 2006