

A076830


Least square s such that A078142(s) is equal to the nth prime.


1



4, 36, 121, 484, 2809, 11236, 6889, 27556, 29929, 51529, 85849, 744769, 196249, 734449, 727609, 942841, 1203409, 4813636, 1510441, 1885129, 7540516, 8048569, 4932841, 4108729, 7946761, 12243001, 18088009, 10608049, 12187081, 10569001
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OFFSET

1,1


LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1000


EXAMPLE

a(1) = 4 since 4 = 2^2 is the least square s such that A078142(s) = 2, the first prime.
a(2) = 36 since 36 = 6^2 is the least square s such that A078142(s) = 3, the second prime.


MATHEMATICA

s[n_] := Total[Ceiling[Sqrt[(p = FactorInteger[n][[;; , 1]])]]^2  p]; m = 30; seq = Table[0, {m}]; c = 0; k = 1; While[c < m, n = s[k^2]; If[PrimeQ[n] && (i = PrimePi[n]) <= m && seq[[i]] == 0, c++; seq[[i]] = k^2]; k++]; seq (* Amiram Eldar, Dec 11 2019 *)


CROSSREFS

Cf. A078142.
Sequence in context: A193874 A254939 A038688 * A144298 A072109 A045490
Adjacent sequences: A076827 A076828 A076829 * A076831 A076832 A076833


KEYWORD

nonn


AUTHOR

Jason Earls, Nov 21 2002


EXTENSIONS

Name edited by Amiram Eldar, Dec 11 2019


STATUS

approved



