login
A389312
Powers k^m, m > 1, such that k is in A303946 and A053669(k) > A006530(k).
3
144, 324, 576, 1728, 2304, 2916, 3600, 5184, 5832, 8100, 9216, 11664, 13824, 14400, 20736, 22500, 26244, 32400, 36864, 57600, 72900, 82944, 90000, 104976, 110592, 129600, 147456, 157464, 176400, 186624, 202500, 216000, 230400, 236196, 248832, 291600, 331776, 360000
OFFSET
1,1
COMMENTS
Intersection of A389864 and A055932 = A380446 \ A365308.
Union of disjoint subsequences A389226 and A389394.
A380446 is the union of this sequence and A365308, both disjoint.
A369374 is the union of this sequence, A365308, and A377854, all disjoint.
A363814 is the union of this sequence, A365308, A377854, and A380543, all disjoint.
EXAMPLE
Table of n, a(n) for n = 1..12:
n a(n)
------------------------------------
1 144 = 12^2 = 2^4 * 3^2
2 324 = 18^2 = 2^2 * 3^4
3 576 = 24^2 = 2^6 * 3^2
4 1728 = 12^3 = 2^6 * 3^3
5 2304 = 48^2 = 2^8 * 3^2
6 2916 = 54^2 = 2^2 * 3^6
7 3600 = 60^2 = 2^4 * 3^2 * 5^2
8 5184 = 72^2 = 2^6 * 3^4
9 5832 = 18^3 = 2^3 * 3^6
10 8100 = 90^2 = 2^2 * 3^4 * 5^2
11 9216 = 96^2 = 2^10 * 3^2
12 11664 = 108^2 2^4 * 3^6
MATHEMATICA
nn = 360000; mm = Sqrt[nn]; i = 1; k = 2; fQ[x_] := And[#[[1, 1]] == 2, Length[#] > 1, CountDistinct[#[[;; , -1]] ] > 1, Union@ Differences@ Map[PrimePi, #[[;; , 1]] ] == {1}] &[FactorInteger[x]]; MapIndexed[Set[S[First[#2]], #1] &, Select[Range[mm], fQ]]; Union@ Reap[While[j = 2; While[S[i]^j < nn, Sow[S[i]^j]; j++]; j > 2, k++; i++] ][[-1, 1]]
KEYWORD
nonn
AUTHOR
Michael De Vlieger, Oct 31 2025
STATUS
approved