OFFSET
1,5
COMMENTS
Starting from x=n, iterate the map x -> A332893(x) which divides even numbers by 2, and for odd n changes every 4k+1 prime in their prime factorization to 4k+3 prime and vice versa (except 3 -> 2), like in A332819. a(n) counts the numbers of the form 4k+1 encountered until 1 has been reached, which is also included in the count when n > 1. This count includes also n itself when it is of the form 4k+1 (A016813) and larger than 1.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..65537
FORMULA
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 04 2020
STATUS
approved