OFFSET
1,2
COMMENTS
Numbers k >= 0 for which A328578(k) = A257993(A276086(A276086(k))) = 2, where A276086 converts the primorial base expansion of k into its prime product form, and A257993 returns the index of the least prime not present in its argument. - The original, equivalent definition.
Numbers k for which A276087(k) is an even number, but not a multiple of three.
LINKS
FORMULA
{k | A358840(k) == 1}. - Antti Karttunen, Dec 02 2022
PROG
(PARI)
A257993(n) = { for(i=1, oo, if(n%prime(i), return(i))); }
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
isA328632(n) = (2==A328578(n));
(PARI)
isA326832(n) = A358841(n);
A358841(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (1==(m%6)); }; \\ Antti Karttunen, Dec 12 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 27 2019
EXTENSIONS
Definition replaced with a simpler one and the original definition moved to the comments section by Antti Karttunen, Dec 03 2022
STATUS
approved