A306964 Trajectory of 2 under repeated application of x -> A306958(x).

2, 90, 3628801, 3780821, 4234421, 16030, 151932, 3659870, 6230161, 303231, 2261, 151390, 3659781, 6230170, 756822, 2600820, 1965783, 6230170, 756822, 2600820, 1965783, 6230170, 756822, 2600820, 1965783, 6230170, 756822, 2600820, 1965783

Offset

1,1

Comments

The trajectory converges to the cycle of length 4 given in A306959. See A306958 for further information.

References

P. Kiss, A generalization of a problem in number theory, Math. Sem. Notes Kobe Univ., 5 (1977), no. 3, 313-317. MR 0472667 (57 #12362).

Links

Table of n, a(n) for n=1..29.

P. Kiss, A generalization of a problem in number theory, [Hungarian], Mat. Lapok, 25 (No. 1-2, 1974), 145-149.

H. J. J. te Riele, Iteration of number-theoretic functions, Nieuw Archief v. Wiskunde, (4) 1 (1983), 345-360. See Example I.1.d.

Mathematica

a[n_]:=Total[Binomial[10, #]*#!&/@IntegerDigits[n]]; NestWhileList[a, 2, UnsameQ, All] (* Ray Chandler, Nov 30 2023 *)

Crossrefs

Cf. A306958, A306959.

Sequence in context: A342329 A377135 A306760 * A138583 A193747 A242176

Adjacent sequences: A306961 A306962 A306963 * A306965 A306966 A306967

Keyword

nonn,base

Author

N. J. A. Sloane, Mar 18 2019

Status

approved