A168047 - OEIS

%I #10 May 17 2024 03:28:33

%S 1,2,3,4,12,25,30,470,1224,57843,145122,16805481,5285171382

%N Numbers k that divide the k-th isolated number.

%F {k: k | A167706(k)}.

%o (PARI) lista(pmax) = {my(p1 = 2, p2 = 3, c = 1); print1(c, ", "); forprime(p3 = 5, pmax, if(p2 == p1 + 2, c++; if(!((p1+1)%c), print1(c, ", "))); if(p2 != p1 + 2 && p2 != p3 - 2, c++); p1 = p2; p2 = p3);} \\ _Amiram Eldar_, May 17 2024

%Y Cf. A167706.

%K nonn,more

%O 1,2

%A _Juri-Stepan Gerasimov_, Nov 17 2009

%E Definition and a(6), a(7) corrected; 4 terms added - _R. J. Mathar_, Jun 04 2010

%E a(12)-a(13) from _Amiram Eldar_, May 17 2024