A033916 - OEIS

%I #14 Jul 29 2021 09:31:16

%S 537,1557,8313,16493,18149,55849,145029,211581,334577,436915,3445721,

%T 20866521,31321817,66133149,143953833,472294345,80640391857

%N Numbers k such that s(k) + s(k+1) + ... + s(k+14) = t(k) + t(k+1) + ... + t(k+14).

%C a(18) > 10^11. - _Donovan Johnson_, Aug 15 2011

%F Here s(k) = sigma(k) - k, t(k) = |s(k) - k|.

%o (PARI) l=vector(15,n,abs(sigma(n)-2*n)-sigma(n)+n);l[15]=0;sc=sum(n=1,15,l[n]);for(n=15,10000000,m=sigma(n)-2*n;d=abs(m)-m-n;i=(n-1)%15+1;sc=sc-l[i]+d;l[i]=d;if(sc==0,print1(n-14,","))) \\ C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 02 2005

%Y Cf. A001065, A033880, A033910, A033911, A033912, A033913, A033914.

%K nonn,more

%O 1,1

%A _Naohiro Nomoto_

%E More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 02 2005

%E a(12)-a(17) from _Donovan Johnson_, Aug 15 2011