90902

Appears in sequences

• a(n) = (9*n+4)*(9*n+5).at n=33A177073
• Consider a number of k digits n = d_(k)*10^(k-1) + d_(k-1)*10^(k-2) + … + d_(2)*10 + d_(1). Sequence lists the numbers n such that Sum_{i=1..k-1}{phi(Sum_{j=1..i}{d_(j)*10^(j-1)})} = Sum_{i=1..k-1}{sigma(Sum_{j=1..i}{d_(k-j+1)*10^(i-j)})} (see example below).at n=26A244069
• a(n) = (A022010(n) - 179)/210.at n=10A357889