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A104192
a(n) = prime(n) - phi(n).
0
1, 2, 3, 5, 7, 11, 11, 15, 17, 25, 21, 33, 29, 37, 39, 45, 43, 55, 49, 63, 61, 69, 61, 81, 77, 89, 85, 95, 81, 105, 97, 115, 117, 123, 125, 139, 121, 145, 143, 157, 139, 169, 149, 173, 173, 177, 165, 207, 185, 209, 201, 215, 189, 233, 217, 239, 233, 243, 219, 265, 223
OFFSET
1,2
MATHEMATICA
a== Table[Prime[n] - EulerPhi[n], {n, 1, 200}]
PROG
(PARI) a(n) = prime(n) - eulerphi(n);
CROSSREFS
Sequence in context: A060264 A219429 A256457 * A290639 A262061 A104193
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Mar 12 2005
STATUS
approved