

A111440


Squares of the form semiprime(n) + prime(n).


2



9, 25, 64, 81, 400, 576, 1024, 1296, 2304, 2704, 4096, 7225, 7744, 10816, 14884, 15376, 19044, 20736, 22500, 25600, 26244, 28900, 33124, 35344, 39601, 41616, 46656, 47961, 48400, 52900, 55225, 89401, 91204, 96100, 99856, 114921, 136900
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OFFSET

1,1


LINKS



EXAMPLE

The first 3 semiprimes are {4,6,9} and the first 3 primes are {2,3,5}. The second term in each are {6,3} whose sum is 9, a square.  _Robert G. Wilson v_


MATHEMATICA

sp = Select[ Range[10^5], Plus @@ Last /@ FactorInteger@ # == 2 &]; s = Select[ Range@Length@sp, IntegerQ[ Sqrt[sp[[ # ]] + Prime@# ]] &]; sp[[s]] + Prime[s]; (* _Robert G. Wilson v_ *)


CROSSREFS



KEYWORD

nonn


AUTHOR

_Giovanni Teofilatto_, Nov 14 2005


EXTENSIONS

More terms from _Robert G. Wilson v_, Nov 18 2005


STATUS

approved



