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A063474
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Half totient of 2^n+1.
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1
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1, 2, 3, 8, 10, 24, 42, 128, 162, 400, 682, 1920, 2730, 6272, 9900, 32768, 43690, 93312, 174762, 493440, 682668, 1672704, 2796202, 8257536, 10125000, 26153088, 42384060, 126322560, 175923744, 380160000, 715827882, 2144133120
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Harry J. Smith, Table of n, a(n) for n=1,...,250
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FORMULA
| a(n)=A023022[A000051(n)]
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PROG
| (PARI) H(n)=eulerphi(n)/2; j=[]; for(n=1, 40, j=concat(j, H(2^n+1))); j
(PARI) { for (n=1, 250, write("b063474.txt", n, " ", eulerphi(2^n + 1)/2) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 22 2009]
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CROSSREFS
| Cf. A023022, A000051.
Sequence in context: A034437 A175715 A138880 * A163492 A025562 A107401
Adjacent sequences: A063471 A063472 A063473 * A063475 A063476 A063477
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KEYWORD
| nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Jul 27 2001
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