Friday, May 31, 2024

A373291 Contribution to the OEIS



A373291
This is one of my favorite sequences.

Least perfect power of n containing some decimal digit of n.
+30
0
1, 32, 243, 64, 25, 36, 16807, 32768, 729, 100, 121, 144, 169, 196, 225, 256, 4913, 5832, 361, 400, 441, 234256, 529, 13824, 625, 676, 729, 784, 24389, 900, 961, 1024, 35937, 39304, 1225, 1296, 1369, 54872, 59319, 1600 (listgraphrefslistenhistoryedittextinternal format)
OFFSET
1,2
COMMENTS
"Perfect power of n" here means n^k with k>1. The sequence gives the value of n^k, not the value of k. - N. J. A. Sloane, May 31 2024
LINKS
FORMULA
a(n) = n^A253600(n).
EXAMPLE
For n=12, 12^2=144 contains digit 1 from n so that a(12) = 144.
MATHEMATICA
seq={}; Do[k=1; Until[ ContainsAny[IntegerDigits[n], IntegerDigits[n^k] ], k++ ]; AppendTo[seq, n^k] , {n, 40}]; seq
PROG
(PARI) a(n) = my(sd = Set(vecsort(digits(n))), k=2); while (#setintersect(sd, Set(vecsort(digits(n^k)))) == 0, k++); n^k; \\ Michel Marcus, May 31 2024
CROSSREFS
KEYWORD
nonn,base,new
AUTHOR
James C. McMahon, May 30 2024
STATUS
approved

No comments:

Post a Comment

1679 - One important message sent from Earth 31 years ago

In 1974 an interstellar radio transmission was broadcast to the  globular cluster   Messier 13   from the Arecibo radio telescope in Puerto ...

Popular in last 30 days