A349063 - OEIS

%I #9 Nov 07 2021 06:30:38

%S 2988,4067,7595,13572,14651,24156,25235,27684,28763,34740,35819,38268,

%T 39347,41327,46403,48852,49931,56987,59436,66492,70020,78155,81683,

%U 87660,88739,91188,98244,99323,101772,102851,108828,109907,112356,113435,119412,120491,122940

%N Numbers k such that k and k+1 have the same sum of powerful divisors (A183097) and this sum is larger than 1.

%C Numbers k such that A183097(k) = A183097(k+1) > 1.

%H Amiram Eldar, <a href="/A349063/b349063.txt">Table of n, a(n) for n = 1..10000</a>

%e 2988 is a term since = A183097(2988) = A183097(2989) = 50 > 1.

%t f[p_, e_] := (p^(e + 1) - 1)/(p - 1) - p; s[1] = 1; s[n_] := Times @@ f @@@ FactorInteger[n]; q[n_] := (s1 = s[n]) > 1 && s1 == s[n + 1]; Select[Range[10^5], q]

%Y Cf. A183097.

%Y Similar sequences: A002961, A064115, A064125, A293183, A306985.

%K nonn

%O 1,1

%A _Amiram Eldar_, Nov 07 2021