# [seqfan] Re: A036322

Allan Wechsler acwacw at gmail.com
Wed Jun 25 20:51:02 CEST 2014

```6 is not prime. The factors have to be elements of A020469.

On Wed, Jun 25, 2014 at 2:31 PM, Harvey P. Dale <hpd at hpdale.org> wrote:

>         There is something I don't understand about the above sequence.
>  According to the definition, the prime factors of its terms can have
> digits of either 6 or 7.  But the first term is 49, i.e., 7*7, rather than
> 36, i.e., 6*6.  And 42 is also missing, i.e., 6*7.  For the first 50 terms
> of the sequence, I get the following (which is drastically different than
> what is provided in the current OEIS version): 36, 42, 49, 216, 252, 294,
> 343, 396, 402, 456, 462, 469, 532, 539, 1296, 1512, 1764, 2058, 2376, 2401,
> 2412, 2736, 2772, 2814, 3192, 3234, 3283, 3724, 3773, 3996, 4002, 4056,
> 4062, 4356, 4422, 4489, 4596, 4602, 4656, 4662, 4669, 4732, 4739, 5016,
> 5082, 5092, 5159, 5362, 5369, 5432.  I used the following Mma program to
> generate these terms:
>
> With[{ss=Flatten[Table[FromDigits/@Tuples[{6,7},n],{n,4}]]},Take[Union[Flatten[Table[Times@
> @@Tuples[ss,n],{n,2,4}]]],90]]
> Am I misunderstanding something?
>         Best,
>         Harvey
>
>
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>
```