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A147551 Minimum of A000010(m) where m is an n-digit number. 2
1, 4, 32, 240, 2304, 20736, 184320, 1843200, 17740800, 170311680, 1642291200, 16057958400, 153280512000, 1532805120000, 15229951672320, 147149291520000, 1456777986048000, 14214621560832000, 140724753452236800 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = A000010(A147550(n))
MATHEMATICA
a[n_]:=Min[EulerPhi[Range[10^(n-1), 10^n-1]]]; Do[Print[a[n]], {n, 10}]
PROG
(PARI) a(n)=if(n<3, return(3*n-2)); my(t=eulerphi(10^(n-1))); forstep(k=(10^n\300+1)*30, 10^n, 30, if(eulerphi(k)<t, t=eulerphi(k))); t \\ Charles R Greathouse IV, Feb 21 2013
CROSSREFS
Cf. A147550.
Sequence in context: A301438 A331334 A301779 * A316803 A299649 A317520
KEYWORD
base,nonn
AUTHOR
Farideh Firoozbakht, Nov 23 2008
EXTENSIONS
More terms from Hagen von Eitzen, Jun 05 2009
Offsets in b-file corrected by N. J. A. Sloane, Aug 31 2009
STATUS
approved

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Last modified February 21 15:59 EST 2024. Contains 370237 sequences. (Running on oeis4.)