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

0, 0, 0, 18, 0, 17, 0, 214, 24, 15, 0, 211, 0, 13, 20, 2206, 0, 215, 0, 205, 16, 189, 0, 2199, 30, 187, 306, 199, 0, 205, 0, 22190, 278, 183, 22, 2197, 0, 181, 274, 2185, 0, 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

Offset

1,4

Comments

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

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Mathematica

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

Prog

(Python)
from sympy import factorint
def A289660(n):
    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

Crossrefs

Cf. A037274, A037276, A080670.

Sequence in context: A198810 A347532 A243911 * A096306 A335187 A231962

Adjacent sequences: A289657 A289658 A289659 * A289661 A289662 A289663

Keyword

nonn,base

Author

N. J. A. Sloane, Jul 24 2017

Status

approved