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A278260
Least number with the same prime signature as {the n-th quarter-square}+1.
3
1, 2, 2, 2, 2, 6, 2, 2, 6, 6, 2, 2, 2, 12, 6, 6, 2, 6, 6, 2, 6, 6, 6, 6, 2, 30, 6, 2, 2, 6, 2, 2, 30, 30, 2, 12, 8, 6, 6, 2, 2, 30, 2, 6, 12, 30, 6, 2, 2, 6, 30, 2, 6, 30, 2, 6, 6, 6, 6, 6, 12, 30, 6, 12, 6, 30, 2, 6, 6, 6, 6, 2, 6, 30, 30, 12, 2, 6, 6, 2, 6, 12, 2, 6, 6, 60, 6, 6, 6, 6, 6, 6, 30, 210, 6, 6, 6, 6, 30, 6, 2, 6, 6, 6, 6, 30, 6, 2, 2, 30, 30, 2, 6
OFFSET
1,2
COMMENTS
Great majority of the terms seem to be primorials (A002110), 9149 of the first 10000, meaning also that the corresponding terms in A033638 are squarefree (A005117).
LINKS
FORMULA
a(n) = A046523(A033638(n)).
PROG
(Scheme) (define (A278260 n) (A046523 (A033638 n)))
CROSSREFS
Cf. A278162 (bisection).
Cf. also A278254, A278259.
Sequence in context: A103794 A273258 A073124 * A070877 A156717 A198889
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 22 2016
STATUS
approved