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A166256
Numbers n with property that n^2 is a sum of some 70 successive primes.
2
200, 322, 770, 982, 2848, 5552, 6622, 7236, 7292, 7972, 8472, 8750, 9166, 9350, 9708, 10272, 11922, 12242, 13246, 13280, 13648, 13728, 14736, 16552, 17134, 17556, 17800, 18294, 18410, 19296, 22352, 22570, 23454, 24120, 24340, 24424, 24432, 26194, 28740, 32248
OFFSET
1,1
COMMENTS
Indices of the initial primes of series of 70 successive primes are (A166255): 71,201,1024,1594,10915,36934,51050,60054,60914,71822,80331,85230,92916.
EXAMPLE
200^2=prime(71)+...+prime(71+69),
322^2=prime(201)+...+prime(201+69),
770^2=prime(1024)+...+prime(1024+69).
PROG
(PARI) lista(nn) = {pr = primes(nn); for (i = 1, nn-69, s = sum(k=i, i+69, pr[k]); if (issquare(s), print1(sqrtint(s), ", ")); ); } \\ Michel Marcus, Oct 15 2013
CROSSREFS
Cf. A166255.
Sequence in context: A124472 A247399 A078492 * A252059 A004966 A117412
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 10 2009
EXTENSIONS
a(38)-a(40) from Michel Marcus, Oct 15 2013
STATUS
approved