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A166262
Numbers n with property that n^2 is a sum of some 120 successive primes.
1
3734, 3846, 8660, 10602, 13248, 13690, 14318, 14936, 17934, 20458, 23902, 27614, 27704, 29176, 30942, 31064, 34238, 35070, 36216, 38346, 38532, 38774, 42236, 42428, 43190, 43742, 43794, 47308, 47622, 49708, 56070, 57036, 58856, 65692, 66122, 66940, 68016
OFFSET
1,1
COMMENTS
n^2=sum(prime(k),k=m,m+119); corresponding values of m: 10917, 11527, 50923, 73894, 111468, 118436, 128662, 139123, 195234 (A166261).
EXAMPLE
a(1)=3734: 3734^2=sum[Prime[i], {i,10917,10917+119}],
a(2)=3846: 3846^2=sum[Prime[i], {i,11527,11527+119}].
MATHEMATICA
Select[Sqrt[#]&/@(Total/@Partition[Prime[Range[5*10^6]], 120, 1]), IntegerQ] (* Harvey P. Dale, Jul 17 2019 *)
PROG
(PARI) lista(nn) = {pr = primes(nn); for (i=1, nn-119, s = sum(k=i, i+119, pr[k]); if (issquare(s), print1(sqrtint(s), ", ")); ); } \\ Michel Marcus, Oct 15 2013
CROSSREFS
Cf. A166261.
Sequence in context: A251206 A038012 A020410 * A340403 A235977 A235243
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 10 2009
EXTENSIONS
a(35)-a(37) from Michel Marcus, Oct 15 2013
STATUS
approved