Question 81
In the sequence
$$
77492836181624186886128 \ldots,
$$
all of the digits except the first two are obtained by writing down the products of pairs of consecutive digits. Prove that infinitely many 6 s appear in the sequence.
$$
77492836181624186886128 \ldots,
$$
all of the digits except the first two are obtained by writing down the products of pairs of consecutive digits. Prove that infinitely many 6 s appear in the sequence.