a(n) is the smallest number whose English name has the letter "r" in the n-th position, or -1 if no such number exists.

A164796

a(n) is the smallest number whose English name has the letter "r" in the n-th position, or -1 if no such number exists.

Terms

    a(0) =-1a(1) =-1a(2) =0a(3) =4a(4) =1000000000000a(7) =43a(8) =23a(9) =24a(10) =74a(12) =103a(13) =104a(14) =303a(15) =304a(16) =3004a(17) =143a(18) =123a(19) =124a(20) =174a(21) =324a(22) =374a(23) =1103a(24) =1104a(25) =1303a(26) =1304a(27) =3303a(28) =1143a(29) =1123a(30) =1124a(31) =1174a(32) =1324

External references