login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A272322
Numbers n such that n^n does not contain all ten decimal digits.
0
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 22, 27, 28, 30, 34, 40, 100, 1000, 10000, 100000, 1000000
OFFSET
1,3
COMMENTS
A240963 is a subsequence.
A011557 is a subsequence. So this sequence is obviously infinite.
Conjecture: the only values > 40 are the powers of 10. - Franklin T. Adams-Watters, Apr 29 2016
EXAMPLE
27 is a term because 27^27 = 443426488243037769948249630619149892803 does not contain digit 5.
28 is a term because 28^28 = 33145523113253374862572728253364605812736 does not contain digit 9.
MATHEMATICA
{0}~Join~Select[Range[10^4], Times @@ DigitCount[#^#] == 0 &] (* Michael De Vlieger, Apr 25 2016 *)
PROG
(PARI) isA171102(n) = 9<#vecsort(Vecsmall(Str(n)), , 8);
lista(nn) = for(n=0, nn, if(!isA171102(n^n), print1(n, ", ")));
(PARI) is(n)=#Set(digits(n^n))<=9 \\ Charles R Greathouse IV, Apr 29 2016
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Altug Alkan, Apr 25 2016
EXTENSIONS
a(31) from Charles R Greathouse IV, Apr 29 2016
a(32) from Charles R Greathouse IV, May 03 2016
STATUS
approved