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Numbers n such that omega(lambda(n)) = lambda(omega(n)).
1

%I #10 May 21 2017 21:33:00

%S 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,

%T 84,85,90,96,105,110,114,126,128,130,132,136,138,140,150,156,160,165,

%U 168,174,180,182,190,192,195,210,220,222,228,230,234,238,246

%N Numbers n such that omega(lambda(n)) = lambda(omega(n)).

%H G. C. Greubel, <a href="/A173946/b173946.txt">Table of n, a(n) for n = 1..1000</a>

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

%e 174 is in the sequence because omega(lambda(174)) = omega(28) = 2 , lambda(omega(174))

%e = lambda(3) = 2.

%p 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:

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

%Y Cf. A001221 A002322.

%K nonn

%O 1,2

%A _Michel Lagneau_, Nov 26 2010