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A321539
3^n with digits rearranged into nonincreasing order.
14
1, 3, 9, 72, 81, 432, 972, 8721, 6651, 98631, 99540, 777411, 544311, 9543321, 9987642, 98744310, 76443210, 964321110, 988744320, 7666422111, 8876444310, 65433321000, 99865331100, 98877443211, 988654432221, 988876444320, 9888655432221
OFFSET
0,2
FORMULA
a(n) = A004186(A000244(n)). - Michel Marcus, Nov 10 2022
MATHEMATICA
A321539[n_]:=FromDigits[ReverseSort[IntegerDigits[3^n]]]; Array[A321539, 40, 0] (* Paolo Xausa, Aug 10 2023 *)
PROG
(Python)
def A321539(n): return int(''.join(sorted(str(3**n), reverse=True))) # Chai Wah Wu, Nov 10 2022
CROSSREFS
The following are parallel families: A000079 (2^n), A004094 (2^n reversed), A028909 (2^n sorted up), A028910 (2^n sorted down), A036447 (double and reverse), A057615 (double and sort up), A263451 (double and sort down); A000244 (3^n), A004167 (3^n reversed), A321540 (3^n sorted up), A321539 (3^n sorted down), A163632 (triple and reverse), A321542 (triple and sort up), A321541 (triple and sort down).
Cf. A004186.
Sequence in context: A318030 A018564 A004167 * A163632 A321541 A102322
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Nov 19 2018
STATUS
approved