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A127720
Floor of square root of sum of squares of n odd consecutive primes.
5
3, 5, 9, 14, 19, 25, 31, 39, 48, 57, 68, 80, 90, 102, 115, 129, 143, 157, 173, 187, 203, 220, 237, 256, 275, 294, 313, 331, 350, 372, 394, 418, 440, 465, 488, 513, 538, 564, 590, 616, 642, 670, 697, 724, 751, 780, 811, 843, 873
OFFSET
1,1
FORMULA
a(n) = A000196(A024450(n+1) - 4). - R. J. Mathar, Jan 28 2007
MAPLE
A024450 := proc(n) local i ; add((ithprime(i))^2, i=1..n) ; end: Ax := proc(n) A024450(n+1)-4 ; end: A000196 := proc(n) floor(sqrt(n)) ; end: A127720 := proc(n) A000196(Ax(n)) ; end: for n from 1 to 30 do printf("%d, ", A127720(n)) ; od ; # R. J. Mathar, Jan 28 2007
MATHEMATICA
a = {}; k = 0; Do[k = k + (Prime[x])^2; AppendTo[a, Floor[Sqrt[k]]], {x, 2, 50}]; a
Module[{nn=50}, Floor[Sqrt[#]]&/@Accumulate[Prime[Range[2, nn+1]]^2]] (* Harvey P. Dale, Jul 27 2017 *)
CROSSREFS
Sequence in context: A372639 A082874 A266250 * A118002 A069533 A054066
KEYWORD
nonn
AUTHOR
Artur Jasinski, Jan 25 2007
STATUS
approved