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A289660 a(n) = A037276(n) - n. 2

%I

%S 0,0,0,18,0,17,0,214,24,15,0,211,0,13,20,2206,0,215,0,205,16,189,0,

%T 2199,30,187,306,199,0,205,0,22190,278,183,22,2197,0,181,274,2185,0,

%U 195,0,2167,290,177,0,22175,28,205,266,2161,0,2279,456,2171,262,171,0,2175,0,169,274,222158,448,2245,0

%N a(n) = A037276(n) - n.

%C The fact that a(n)>0 if n is composite shows that (unlike A080670), A037276 has no nontrivial fixed points (nor any cycles).

%H Vincenzo Librandi, <a href="/A289660/b289660.txt">Table of n, a(n) for n = 1..1000</a>

%t FromDigits@Flatten@IntegerDigits[Table[#1,{#2}]&@@@FactorInteger@#]-#&/@Range@54 (* _Vincenzo Librandi_, Jul 25 2017 *)

%o (Python)

%o from sympy import factorint

%o def A289660(n):

%o return 0 if n == 1 else int(''.join(map(lambda x: str(x[0])*x[1],sorted(factorint(n).items())))) - n # _Chai Wah Wu_, Jul 25 2017

%Y Cf. A037274, A037276, A080670.

%K nonn,base

%O 1,4

%A _N. J. A. Sloane_, Jul 24 2017

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Last modified November 14 15:00 EST 2019. Contains 329126 sequences. (Running on oeis4.)