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A089580 Total number of exact powers below 10^n (counting duplicates). 2
3, 15, 49, 143, 406, 1174, 3507, 10674, 32965, 102716, 321797, 1011533, 3186389, 10050743, 31730134, 100228040, 316713623, 1001037546, 3164497349, 10004755374, 31632975598, 100021893194, 316274794666, 1000101078148 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

E.g. 16 = 2^4 = 4^2 counts double, 256 = 2^8 = 4^4 = 16^2 counts three times.

MATHEMATICA

Table[lim=10^n-1; Sum[Floor[lim^(1/k)]-1, {k, 2, Floor[Log[2, lim]]}], {n, 30}] - T. D. Noe (noe(AT)sspectra.com), Nov 16 2006

CROSSREFS

Cf. A001597.

Cf. A089579 (not counting duplicates).

Sequence in context: A135622 A061316 A124161 * A034564 A012203 A112586

Adjacent sequences:  A089577 A089578 A089579 * A089581 A089582 A089583

KEYWORD

nonn

AUTHOR

Martin Renner (martin.renner(AT)gmx.net), Dec 29 2003

EXTENSIONS

2 more terms from Martin Renner (martin.renner(AT)gmx.net), Oct 02 2004

More terms from T. D. Noe (noe(AT)sspectra.com), Nov 16 2006

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.