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A296091
a(1) = 1 and for n > 1, the least number with the same prime signature as sigma(n)-1.
5
1, 2, 2, 6, 2, 2, 2, 6, 12, 2, 2, 8, 2, 2, 2, 30, 2, 6, 2, 2, 2, 6, 2, 2, 30, 2, 6, 6, 2, 2, 2, 6, 2, 2, 2, 60, 2, 2, 6, 2, 2, 6, 2, 2, 6, 2, 2, 6, 24, 12, 2, 2, 2, 6, 2, 6, 2, 2, 2, 2, 2, 6, 2, 60, 2, 6, 2, 8, 6, 6, 2, 6, 2, 2, 6, 2, 6, 2, 2, 6, 120, 8, 2, 2, 2, 2, 6, 2, 2, 2, 6, 2, 2, 6, 6, 2, 2, 30, 6, 216, 2, 6, 2, 6, 2
OFFSET
1,2
LINKS
FORMULA
a(1) = 1; for n > 1, a(n) = A046523(A000203(n)-1) = A046523(A039653(n)).
PROG
(Scheme) (define (A296091 n) (if (= 1 n) n (A046523 (+ -1 (A000203 n)))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 07 2017
STATUS
approved