login
A225297
Numbers divisible by their last digit cubed.
4
1, 11, 21, 31, 32, 41, 51, 61, 64, 71, 72, 81, 91, 101, 111, 112, 121, 125, 131, 141, 151, 152, 161, 171, 181, 191, 192, 201, 211, 216, 221, 231, 232, 241, 243, 251, 261, 271, 272, 281, 291, 301, 311, 312, 321, 331, 341, 351, 352, 361, 371, 375, 381, 384, 391
OFFSET
1,2
COMMENTS
Numbers k such that (k mod 10)^3 | k.
All numbers ending in 1 are trivially included in this sequence.
The sequence is { 1+10k, 32 + 40k, 243 + 270k, 64 + 320k, 125 + 250k, 216 + 1080k, 3087 + 3430k, 2048 + 2560k, 729 + 7290k ; k = 0,1,2,...}. - M. F. Hasler, Jan 31 2016
The asymptotic density of this sequence is 2201597407/16003008000 = 0.137573... . - Amiram Eldar, Aug 08 2023
LINKS
Christian N. K. Anderson, Table of n, a(n) for n = 1..10000
EXAMPLE
a(16) = 112 is divisible by 2^3.
MATHEMATICA
Select[Range[400], (m = Mod[#, 10]) > 0 && Divisible[#, m^3] &] (* Amiram Eldar, Aug 08 2023 *)
PROG
(R) x=0; y=rep(0, 100); len=0; isint<-function(x) x==as.integer(x); while(len<100) if((x=x+1)%%10>0) if(isint(x/(x%%10)^3)) y[(len=len+1)]=x
(PARI) is(n)=n%10&&n%(n%10)^3==0 \\ M. F. Hasler, Jan 31 2016
CROSSREFS
KEYWORD
nonn,base
STATUS
approved