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A378987
Odd bisection of A083254, where A083254(n) = 2*phi(n)-n.
2
1, 1, 3, 5, 3, 9, 11, 1, 15, 17, 3, 21, 15, 9, 27, 29, 7, 13, 35, 9, 39, 41, 3, 45, 35, 13, 51, 25, 15, 57, 59, 9, 31, 65, 19, 69, 71, 5, 43, 77, 27, 81, 43, 25, 87, 53, 27, 49, 95, 21, 99, 101, -9, 105, 107, 33, 111, 61, 27, 73, 99, 37, 75, 125, 39, 129, 83, 9, 135, 137, 43, 97, 79, 21, 147, 149, 39, 85, 155, 49, 103, 161, -5, 165
OFFSET
1,3
LINKS
FORMULA
a(n) = A083254(2*n-1).
a(n) = A337544(A064216(n)).
PROG
(PARI)
A083254(n) = (2*eulerphi(n)-n);
A378987(n) = A083254(n+n-1);
CROSSREFS
Cf. also A378986 (the other bisection).
Sequence in context: A318377 A186203 A002633 * A070554 A076842 A077862
KEYWORD
sign
AUTHOR
Antti Karttunen, Dec 14 2024
STATUS
approved