A257246 Even bisection of A257244: a(n) = A257244(2n).

2, 3, 3, 3, 3, 5, 3, 3, 3, 5, 7, 7, 3, 3, 7, 3, 5, 3, 5, 5, 11, 3, 13, 3, 13, 5, 11, 3, 7, 3, 13, 3, 13, 3, 5, 5, 11, 23, 3, 7, 3, 7, 3, 7, 3, 31, 3, 7, 13, 3, 7, 5, 7, 3, 31, 31, 3, 13, 41, 5, 3, 7, 19, 3, 7, 41, 41, 3, 19, 7, 29, 5, 3, 13, 11, 5, 3, 19, 3, 5, 5

Offset: 1

Author

Antti Karttunen, Apr 19 2015

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..2047
• Ratio a(n)/A257245(n) plotted with OEIS Plot2-script

Crossrefs

Cf. A020639, A256393, A257244.

Cf. also A257245 (the other bisection), A257247 (gives the positions where both bisections have the same value).

Formula

a(n) = A257244(2n).

a(n) = A020639(A256393(2n)). [Equally, the smallest prime factor of A256393(2n).]

Other identities and observations:

For all n >= 1, a(n) <= A257245(n).