1,1

Complement of A107690 with respect to A199987. Subsequence of A199983 (composite numbers whose multiplicative digital root is 4).

Table of n, a(n) for n=1..41.

Number 122 is in sequence because 1*2*2=4.

Cf. A107690 (primes whose product of digits is 4), A199987 (numbers whose product of digits is 4).

Sequence in context: A298008 A279414 A199987 * A317734 A154046 A000054

Adjacent sequences: A201013 A201014 A201015 * A201017 A201018 A201019

nonn,base

Jaroslav Krizek, Nov 25 2011

approved