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A060272 Distance from n^2 to closest prime. 4
1, 1, 2, 1, 2, 1, 2, 3, 2, 1, 6, 5, 2, 1, 2, 1, 4, 7, 2, 1, 2, 3, 6, 1, 6, 1, 2, 3, 2, 7, 6, 3, 2, 3, 2, 1, 2, 3, 2, 1, 12, 5, 2, 3, 2, 3, 2, 5, 2, 3, 8, 3, 6, 1, 2, 1, 2, 3, 10, 7, 2, 3, 2, 3, 4, 1, 4, 3, 2, 3, 2, 5, 4, 1, 2, 3, 2, 5, 6, 3, 2, 5, 6, 1, 4, 3, 4, 3, 2, 1, 6, 3, 2, 1, 4, 5, 4, 3, 2, 7, 8, 5, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..103.

FORMULA

a(n)=abs(A000290(n)-A113425(n))=abs(A000290(n)-A113426(n)). - Reinhard Zumkeller, Oct 31 2005

EXAMPLE

n=1: n^2=1 is surrounded by primes {-2,2} and 2 is closer, so a(1)=1; n=11: n^2=121 is between primes {113,127} and closer to 127, thus a(11)=6.

MAPLE

[seq(min(nextprime(i^2)-i^2, i^2-prevprime(i^2)), i=2..256)]; n=1 computed separately.

CROSSREFS

Cf. A007491, A053001, A058043, A056927, A053000, A051700, A060268-A060269, A060272, A059959, A059790.

Sequence in context: A219254 A072504 A072499 * A209315 A174713 A129985

Adjacent sequences:  A060269 A060270 A060271 * A060273 A060274 A060275

KEYWORD

nonn

AUTHOR

Labos Elemer, Mar 23 2001

STATUS

approved

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Last modified November 22 19:58 EST 2014. Contains 249822 sequences.