

A171701


The first nfold (at least) intrinsically 2palindromic number (in base ten)


24



3, 8, 18, 24, 48, 60, 120, 120, 180, 336, 360, 360, 720, 720, 720, 840, 1260, 1440, 1680, 1680, 2520, 2520, 2520, 2520, 5040, 5040, 5040, 5040, 5040, 5040, 7560, 7560, 10080, 10080, 10080, 10080, 15120, 15120, 15120, 15120, 30160, 20160, 25200, 25200
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..44.


FORMULA

If d'(k) is the number of divisors of k minus 1 for square k and minus 2 for numbers of the form m^2+m, then a(n) is the first k for which d'(k)/2>n1.


CROSSREFS

Cf. A171702, A171703, A171704, A171705, A171706, A171740, A171741, A171742.
Sequence in context: A319764 A063597 A328054 * A288249 A004210 A247022
Adjacent sequences: A171698 A171699 A171700 * A171702 A171703 A171704


KEYWORD

nonn,base


AUTHOR

James G. Merickel, Dec 16 2009


STATUS

approved



