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A064505
Interchange primes and their squares.
5
1, 4, 9, 2, 25, 6, 49, 8, 3, 10, 121, 12, 169, 14, 15, 16, 289, 18, 361, 20, 21, 22, 529, 24, 5, 26, 27, 28, 841, 30, 961, 32, 33, 34, 35, 36, 1369, 38, 39, 40, 1681, 42, 1849, 44, 45, 46, 2209, 48, 7, 50, 51, 52, 2809, 54, 55, 56, 57, 58, 3481, 60, 3721, 62, 63, 64, 65, 66
OFFSET
1,2
COMMENTS
a(a(n)) = n, self-inverse permutation for the natural numbers.
MATHEMATICA
s=Range[1000]; Do[p=Prime[n]; s[[p]]=p^2, {n, PrimePi[1000]}]; Do[p=Prime[n]; s[[p^2]]=p, {n, PrimePi[Sqrt@1000]}]; s (* Zak Seidov, Jun 29 2008 *)
CROSSREFS
Sequence in context: A374600 A256513 A358916 * A253288 A358971 A358786
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 16 2001
STATUS
approved