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A080732 Smallest distance from n to a prime power (as defined in A246655). 4
1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 2, 2, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 2, 3, 2, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 3, 2, 1, 0, 1, 0, 1, 0, 1, 2, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,21

COMMENTS

a(n)=min (abs(n-k) : where k runs through the prime powers)

LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000

MATHEMATICA

nn = 100; pp = Select[Range[2, Prime[1 + PrimePi[nn]]], Length[FactorInteger[#]] == 1 &]; Table[Min[Abs[n - pp]], {n, nn}] (* T. D. Noe, Mar 14 2012 *)

CROSSREFS

Cf. A051699, A246547, A301295.

There are four different sequences which may legitimately be called "prime powers": A000961 (p^k, k >= 0), A246655 (p^k, k >= 1), A246547 (p^k, k >= 2), A025475 (p^k, k=0 and k >= 2). When you refer to "prime powers", be sure to specify which of these you mean. - N. J. A. Sloane, Mar 24 2018

Sequence in context: A144627 A135929 A080733 * A301295 A215036 A294448

Adjacent sequences:  A080729 A080730 A080731 * A080733 A080734 A080735

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Mar 08 2003

STATUS

approved

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Last modified December 11 22:41 EST 2018. Contains 318052 sequences. (Running on oeis4.)