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A220953
Primes p such that floor(sqrt(2)) + floor(sqrt(3)) + floor(sqrt(5)) + ... + floor(sqrt(p)) is prime.
2
3, 29, 61, 73, 127, 181, 229, 251, 281, 313, 367, 487, 503, 509, 547, 587, 599, 601, 613, 617, 659, 727, 739, 751, 797, 809, 829, 863, 881, 983, 1033, 1061, 1087, 1103, 1153, 1163, 1223, 1277, 1381, 1861, 1871, 2039, 2063, 2099, 2113, 2131, 2203, 2221
OFFSET
1,1
LINKS
MATHEMATICA
ps = Prime[Range[1000]]; t = {}; s = 0; Do[s = s + Floor[Sqrt[p]]; If[PrimeQ[s], AppendTo[t, p]], {p, ps}]; t (* T. D. Noe, Feb 21 2013 *)
PROG
(PARI) s=0; forprime(p=2, 1e4, if(isprime(s+=sqrtint(p)), print1(p", "))) \\ Charles R Greathouse IV, Feb 21 2013
(Magma) [NthPrime(i): i in [1..400] | IsPrime(S) where S is &+[Floor(Sqrt(NthPrime(k))): k in [1..i]]]; // Bruno Berselli, Feb 21 2013
CROSSREFS
Cf. A062048.
Sequence in context: A210360 A049437 A171409 * A031912 A119951 A296246
KEYWORD
nonn
AUTHOR
Daniel J. Hardisky, Feb 20 2013
STATUS
approved