



2048, 9216, 13824, 20736, 25600, 31104, 46656, 50176, 64000, 69984, 104976, 115200, 123904, 157464, 160000, 172800, 173056, 175616, 177147, 225792, 236196, 259200, 288000, 338688, 388800, 400000, 432000, 508032, 557568, 583200, 614656, 627200, 648000, 681472, 720000, 762048, 778752, 790272
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OFFSET

1,1


COMMENTS

Powerful(1) numbers k such that A046660(k) = 10.
These are the "primitive" members of A195069, in the sense that A195059 is the set of numbers k*m where k is in this sequence and m is squarefree and coprime to k.


LINKS

Robert Israel, Table of n, a(n) for n = 1..2528


EXAMPLE

a(3)=13824 is a member because 13824= 2^9*3^3, 9 and 3 are both greater than 1 and (91)+(31)=10.


MAPLE

N:= 10^6: # to get all terms <= N
p:= 1:
for i from 1 to 10 do F[i]:= {} od:
do
p:= nextprime(p);
if p^2 > N then break fi;
for i from min(10, floor(log[p](N))1) to 2 by 1 do F[i]:= F[i] union
select(`<=`, `union`({p^(i+1)}, seq(map(t > p^(i+1j)*t, F[j]), j=1..i1)), N)
od;
F[1]:= F[1] union {p^2};
od:
sort(convert(F[10], list));


CROSSREFS

Cf. A001694, A046660, A195069.
Sequence in context: A234881 A220584 A195069 * A135290 A204837 A100629
Adjacent sequences: A316496 A316497 A316498 * A316500 A316501 A316502


KEYWORD

nonn


AUTHOR

Robert Israel, Jul 04 2018


STATUS

approved



