1,2

For 99 < n < 1000, n belongs to the list if (floor(n/100) mod 10) belongs to the list (i.e., is either 1 or 8).

For 10^(2k+1)-1 < n < 10^(2k+3), where k is a positive integer, n belongs to the list if (floor(n/(10^(2k+1))) mod 100) belongs to the list.

Table of n, a(n) for n=1..58.

Author?, Hindi Numbers

Index entries for sequences related to names of numbers

Cf. A000852.

Sequence in context: A196474 A251258 A101241 * A031258 A277557 A108060

Adjacent sequences: A307970 A307971 A307972 * A307974 A307975 A307976

easy,nonn,word

Sangeet Paul, May 30 2019

approved