OFFSET
0,1
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..1001
FORMULA
a(0) = 16, a(n) = A064216(a(n-1)).
EXAMPLE
Start with a(0) = 16; then after each new term is obtained by doubling the previous term, from which one is subtracted, after which each prime factor is replaced with the previous prime:
16 -> ((2*16)-1) = 31 = p_1, and p_10 = 29, thus a(1) = 29.
29 -> ((2*29)-1) = 57 = 3*19 = p_2 * p_8, and p_1 * p_7 = 2*17 = 34, thus a(2) = 34.
MATHEMATICA
nxt[n_]:=Times@@(NextPrime[#, -1]&/@(Flatten[Table[#[[1]], {#[[2]]}]&/@ FactorInteger[2 n-1]])); NestList[nxt, 16, 50] (* Harvey P. Dale, Apr 04 2015 *)
PROG
CROSSREFS
A246344 gives the terms of the same cycle when going to the opposite direction from 16.
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 24 2014
STATUS
approved