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A348997
a(n) = A348733(A276086(n)), where A348733(n) = gcd(A003959(n), A034448(n)), and A276086 gives the prime product form of primorial base expansion of n.
4
1, 3, 4, 12, 2, 6, 6, 18, 24, 72, 12, 36, 2, 6, 8, 24, 4, 12, 18, 54, 72, 216, 36, 108, 2, 6, 8, 24, 4, 12, 8, 24, 32, 96, 16, 48, 48, 144, 192, 576, 96, 288, 16, 48, 64, 192, 32, 96, 144, 432, 576, 1728, 288, 864, 16, 48, 64, 192, 32, 96, 2, 6, 8, 24, 4, 12, 12, 36, 48, 144, 24, 72, 4, 12, 16, 48, 8, 24, 36, 108, 144
OFFSET
0,2
FORMULA
a(n) = A348733(A276086(n)) = gcd(A348949(n), A348996(n)).
PROG
(PARI) A348997(n) = { my(m1=1, m2=1, p=2); while(n, if(n%p, m1 *= ((1+p)^(n%p)); m2 *= (1+(p^(n%p)))); n = n\p; p = nextprime(1+p)); gcd(m1, m2); };
CROSSREFS
Cf. also A346471 for similar construction. (Compare the scatter plots).
Sequence in context: A045826 A346471 A084200 * A354781 A097850 A238855
KEYWORD
nonn,base,look
AUTHOR
Antti Karttunen, Nov 07 2021
STATUS
approved