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A108221
Primes of the form ceiling(sqrt(prime(n))).
1
2, 2, 3, 3, 5, 5, 5, 7, 7, 7, 7, 11, 11, 11, 11, 11, 13, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 23, 23, 23, 23, 23, 23, 23, 29, 29, 29, 29, 29, 29, 29, 29, 29, 31, 31, 31, 31, 31, 31, 31, 31, 37, 37, 37, 37, 37, 37, 37, 37, 37, 41, 41, 41, 41, 41, 41
OFFSET
1,1
FORMULA
a(n) = ceiling(sqrt(A108222(n))).
MATHEMATICA
Ceiling /@ Sqrt /@ Select[Prime /@ Range[300], PrimeQ[Ceiling[Sqrt[ # ]]] &] (* Ray Chandler, Jul 03 2005 *)
CROSSREFS
Sequence in context: A057872 A059974 A045767 * A169682 A082524 A099961
KEYWORD
easy,nonn
AUTHOR
Giovanni Teofilatto, Jun 16 2005
EXTENSIONS
Extended by Ray Chandler, Jul 03 2005
STATUS
approved