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A053198
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Totients of consecutive pure powers of primes.
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0
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2, 4, 6, 8, 20, 18, 16, 42, 32, 54, 110, 100, 64, 156, 162, 128, 272, 294, 342, 256, 506, 500, 486, 812, 930, 512, 1210, 1332, 1640, 1806, 1024, 1458, 2028, 2162, 2058, 2756, 2500, 3422, 3660, 2048, 4422, 4624, 4970, 5256, 6162, 4374, 6498, 6806, 7832, 4096
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Totients of prime powers are prime powers only for powers of 2.
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FORMULA
| a(n)=A000010[A025475(n)]=Phi(p^k)=(p-1)*p^(k-1)
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EXAMPLE
| The 10th pure power of prime (but not a prime) is 81, so a(10)=EulerPh[81]=54
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CROSSREFS
| A000010, A051593, A001248, A002618, A036689, A053650, A053191, A053192.
Sequence in context: A152491 A133296 A076402 * A179082 A194376 A062897
Adjacent sequences: A053195 A053196 A053197 * A053199 A053200 A053201
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Mar 03 2000
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