A173946 Numbers n such that omega(lambda(n)) = lambda(omega(n)).

1, 3, 4, 5, 6, 8, 10, 12, 15, 16, 17, 20, 24, 32, 34, 40, 42, 48, 51, 64, 66, 68, 70, 78, 80, 84, 85, 90, 96, 105, 110, 114, 126, 128, 130, 132, 136, 138, 140, 150, 156, 160, 165, 168, 174, 180, 182, 190, 192, 195, 210, 220, 222, 228, 230, 234, 238, 246

Offset

1,2

Links

G. C. Greubel, Table of n, a(n) for n = 1..1000

Formula

Numbers n such that A001221 (A002322(n))=A002322(A001221 (n)).

Example

174 is in the sequence because  omega(lambda(174)) = omega(28) = 2 , lambda(omega(174))
  = lambda(3) = 2.

Maple

with(numtheory): for n from 1 to 250 do:if nops(factorset(lambda(n)))= lambda(nops(factorset(n)))then printf(`%d, `, n):else fi:od:

Mathematica

Cases[Range[1000], k_ /; Length[FactorInteger[CarmichaelLambda[k]]] == CarmichaelLambda[Length[FactorInteger [k]]]]

Crossrefs

Cf. A001221 A002322.

Sequence in context: A308192 A026506 A198382 * A051916 A130216 A120162

Adjacent sequences: A173943 A173944 A173945 * A173947 A173948 A173949

Keyword

nonn

Author

Michel Lagneau, Nov 26 2010

Status

approved