A376739 Main diagonal of A376738: a(n) is the n-th number which is the product of n (possibly non-distinct) primes having the same number of decimal digits.

2, 6, 18, 40, 108, 224, 480, 1296, 2688, 5760, 12800, 31104, 64512, 138240, 286720, 614400, 1492992, 3096576, 6422528

Offset

1,1

Comments

See A376738 for more information.

First differs from A101695 at n = 10.

Links

Table of n, a(n) for n=1..19.

Formula

a(n) = A376738(n,n).

Mathematica

A376739[n_] := Module[{m = 2^n - 1}, Do[While[Total[(f = FactorInteger[++m])[[All, 2]]] != n || Length[Union[IntegerLength[f[[All, 1]]]]] > 1], n]; m];
Array[A376739, 15]

Crossrefs

Cf. A101695, A376738.

Sequence in context: A338765 A339149 A101695 * A364672 A014741 A016059

Adjacent sequences: A376736 A376737 A376738 * A376740 A376741 A376742

Keyword

nonn,base,more

Author

Paolo Xausa, Oct 03 2024

Status

approved