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A139408
Numbers n such that phi(n)=d_1!!*d_2!!*...*d_k!! where d_1 d_2 ... d_k is the decimal expansion of n.
0
1, 260, 450, 543, 630, 1164, 2080, 3534, 3640, 4525, 5425, 11176, 13365, 15407, 18333, 24056, 24552, 25064, 25452, 26352, 30660, 37324, 45136, 46160, 46325, 49321, 51742, 52080, 54540, 67122, 76041, 76151, 80325, 81060, 81217, 81532
OFFSET
1,2
EXAMPLE
phi(1111900875)=1!!*1!!*1!!*1!!*9!!*0!!*0!!*8!!*7!!*5!!, so 1111900875 is in the sequence.
CROSSREFS
Sequence in context: A214471 A344238 A344237 * A253504 A154379 A185793
KEYWORD
base,easy,nonn,less
AUTHOR
Farideh Firoozbakht, Apr 19 2008
STATUS
approved