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A062956
a(n) = h(n^2) - h(n), where h(n) is the half-totient function (A023022).
1
2, 3, 8, 5, 18, 14, 24, 18, 50, 22, 72, 39, 56, 60, 128, 51, 162, 76, 120, 105, 242, 92, 240, 150, 234, 162, 392, 116, 450, 248, 320, 264, 408, 210, 648, 333, 456, 312, 800, 246, 882, 430, 528, 495, 1058, 376, 1008, 490, 800, 612, 1352, 477, 1080, 660, 1008
OFFSET
3,1
FORMULA
a(n) = (n-1)*A023022(n), n >= 3.
PROG
(PARI) h(n) = eulerphi(n)/2;
a(n) = h(n^2)-h(n);
CROSSREFS
Sequence in context: A376014 A208449 A346957 * A333375 A289667 A053650
KEYWORD
nonn
AUTHOR
Jason Earls, Jul 22 2001
STATUS
approved