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 A343142 a(n) = sqrt(k*A001414(k)+1) for k in A343141. 1
 7, 11, 19, 23, 41, 41, 71, 103, 113, 151, 223, 199, 239, 199, 241, 307, 487, 379, 491, 419, 1063, 1777, 1013, 881, 1741, 2339, 1409, 3169, 1597, 2287, 1471, 2143, 5009, 2521, 5393, 2351, 3389, 2393, 2663, 2161, 2887, 2969, 4271, 3361, 4889, 2549, 10177, 3191, 3499, 16631, 2753, 10243, 4481, 3691 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Primes that occur more than once in the sequence include 41, 199, 4159, 9437, 10687, 16561, 31249, 40591, 64601, 67339, 91631, 93889, 96799, 111871, 122201, 145417, 180847, 911201. LINKS Robert Israel, Table of n, a(n) for n = 1..450 FORMULA a(n) = sqrt(A343141(n)*A001414(A343141(n))+1). EXAMPLE a(3) = 19 because A343141(3) = 36 and sqrt(36*A001414(36)+1) = 19. MAPLE sopf:= proc(x) local t; add(t[1]*t[2], t=ifactors(x)[2]) end proc: g:= proc(n) local x, y; x:= n*sopf(n)+1;   if issqr(x) then   y:= sqrt(x);   if isprime(y) then return y fi   fi end proc: map(g, [\$1..10^5]); MATHEMATICA Block[{f}, f[n_] := Sqrt[n*Total@ Flatten[ConstantArray @@@ FactorInteger[n]] + 1]; f /@ Select[Range[200000], PrimeQ@ f[#] &] ] (* Michael De Vlieger, Apr 06 2021 *) CROSSREFS Cf. A001414, A343141. Sequence in context: A129899 A129842 A065312 * A235727 A141337 A192187 Adjacent sequences:  A343138 A343139 A343141 * A343143 A343144 A343145 KEYWORD nonn AUTHOR J. M. Bergot and Robert Israel, Apr 06 2021 STATUS approved

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Last modified July 28 22:55 EDT 2021. Contains 346340 sequences. (Running on oeis4.)