OFFSET
1,2
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..50
MATHEMATICA
Select[Range@ 50000, Length@ Union@ IntegerDigits[3 #^2 + 2 # - 1] <= 2 &] (* Giovanni Resta, Sep 04 2019 *)
PROG
(PARI) for(k=1, 1e8, if(#Set(digits(3*k^2+2*k-1))<=2, print1(k", ")))
(Magma) [k:k in [1..10000000]| #Set(Intseq((k+1)*(3*k-1))) le 2]; // Marius A. Burtea, Aug 29 2019
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Seiichi Manyama, Aug 29 2019
EXTENSIONS
a(35)-a(36) from Jinyuan Wang, Aug 30 2019
a(37)-a(40) from Giovanni Resta, Sep 04 2019
STATUS
approved