A349063 Numbers k such that k and k+1 have the same sum of powerful divisors (A183097) and this sum is larger than 1.

2988, 4067, 7595, 13572, 14651, 24156, 25235, 27684, 28763, 34740, 35819, 38268, 39347, 41327, 46403, 48852, 49931, 56987, 59436, 66492, 70020, 78155, 81683, 87660, 88739, 91188, 98244, 99323, 101772, 102851, 108828, 109907, 112356, 113435, 119412, 120491, 122940

Offset

1,1

Comments

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

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

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

Mathematica

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]

Crossrefs

Cf. A183097.

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

Sequence in context: A252571 A231628 A231623 * A108926 A159731 A221725

Adjacent sequences: A349060 A349061 A349062 * A349064 A349065 A349066

Keyword

nonn

Author

Amiram Eldar, Nov 07 2021

Status

approved