A063901 - OEIS

%I #22 Mar 16 2024 18:55:07

%S 1,6,11,17,22,36,63,94,259,632,2161,4441,6268,8305,332790,601702,

%T 3864076,3962954,4393603,11679862,21878360,57402883,101658334,

%U 121475393,124070072,432432118,2068420025,5287649972,13320495021,23871729838,95486769082,138630178659

%N Numbers k such that Sum_{j=1..k} A001065(j) is divisible by k.

%o (PARI) s(n)=sigma(n)-n; for(n=1,10^8,x=sum(k=1,n,s(k)); if(Mod(x,n)==0,print(n)))

%o (PARI) x = 0; for(n=1, 10^10, x = x + sigma(n)-n; if(x%n == 0, print1(n, ", "))) \\ _Ryan Propper_, Jan 13 2008

%Y Cf. A001065.

%K nonn

%O 1,2

%A _Jason Earls_, Aug 29 2001

%E More terms from _Michel ten Voorde_ Jun 20 2003

%E More terms from _Ryan Propper_, Jan 13 2008

%E a(28)-a(30) from _Donovan Johnson_, Dec 29 2008

%E a(31)-a(32) from _Donovan Johnson_, Aug 07 2011

%E Name clarified by _Jon E. Schoenfield_, Nov 17 2018