A039427 - OEIS

%I #12 Jun 30 2021 03:56:45

%S 49,94,149,194,249,294,349,394,409,419,429,439,459,469,479,489,490,

%T 491,492,493,495,496,497,498,549,594,649,694,749,794,849,894,904,914,

%U 924,934,940,941,942,943,945,946,947,948,954,964,974,984,1049,1094

%N Numbers whose base-10 representation has the same nonzero number of 4's and 9's.

%t Select[Range[1100],DigitCount[#,10,4]==DigitCount[#,10,9]>0&] (* _Harvey P. Dale_, Oct 23 2017 *)

%K nonn,base,easy

%O 1,1

%A _Olivier Gérard_