

A061888


Numbers n such that n^2 is the sum of the first k primes for some k.


3




OFFSET

1,1


LINKS

Table of n, a(n) for n=1..6.
G. L. Honaker Jr. and C. Caldwell, Prime Curios!: 9
C. Rivera, PrimePuzzles.Net, Problem 9: Sum of first k primes is perfect square


FORMULA

a(n)^2 = A061890(n).


EXAMPLE

10^2 = 2+3+5+7+11+13+17+19+23, so 10 is in the sequence.


CROSSREFS

Cf. A033997, A033998, A061890.
Sequence in context: A223055 A308488 A180419 * A117803 A199520 A169621
Adjacent sequences: A061885 A061886 A061887 * A061889 A061890 A061891


KEYWORD

nonn


AUTHOR

David W. Wilson, May 12, 2001


EXTENSIONS

468726713734 from Giovanni Resta, May 27 2003
Edited by Ray Chandler, Mar 20 2007


STATUS

approved



