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1,2

a(n) = A000290(A020639(n)).

Table of n, a(n) for n=1..76.

Eric Weisstein's World of Mathematics, Least Prime Factor

Eric Weisstein's World of Mathematics, Square Number

Cf. A088378, A088379.

Cf. A068319.

Cf. A247180.

Sequence in context: A204996 A061369 A291645 * A066048 A103164 A210966

Adjacent sequences: A088374 A088375 A088376 * A088378 A088379 A088380

nonn

Reinhard Zumkeller, Sep 28 2003

approved