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A225804
Arithmetic mean of the first n primes, rounded up.
4
2, 3, 4, 5, 6, 7, 9, 10, 12, 13, 15, 17, 19, 21, 22, 24, 26, 28, 30, 32, 34, 36, 38, 41, 43, 45, 47, 49, 52, 54, 56, 58, 61, 63, 66, 68, 70, 73, 75, 78, 80, 83, 85, 88, 90, 92, 95, 98, 100, 103, 105, 108, 110, 113, 116, 118, 121, 124
OFFSET
1,1
LINKS
Chris K. Caldwell and G. L. Honaker,Jr., Prime Curios! 110
FORMULA
a(n) = ceiling(A007504(n) / n)
EXAMPLE
a(5) = ceiling( (2 + 3 + 5 + 7 + 11)/5) = ceiling(28/5) = 6.
a(6) = ceiling( (2 + 3 + 5 + 7 + 11 + 13)/6) = ceiling(41/6) = 7.
a(7) = ceiling( (2 + 3 + 5 + 7 + 11 + 13 + 17)/7) = ceiling(58/7) = 9.
MAPLE
A007504 := proc(n)
add(ithprime(i), i=1..n) ;
end proc:
A225804 := proc(n)
ceil(A007504(n)/n) ;
end proc: # R. J. Mathar, Jul 28 2013
MATHEMATICA
Table[Ceiling[(Plus@@Prime[Range[n]])/n], {n, 75}] (* Alonso del Arte, Jul 28 2013 *)
CROSSREFS
Cf. A007504, A060620 (rounded down).
Sequence in context: A190209 A048856 A067175 * A049809 A190278 A372477
KEYWORD
nonn,easy
AUTHOR
K. D. Bajpai, Jul 28 2013
STATUS
approved