63869

Appears in sequences

• Numbers k such that k | 10^k + 9^k + 8^k + 7^k.at n=36A057214
• Numbers k such that k | 12^k + 11^k + 10^k + 9^k + 8^k + 7^k + 6^k + 5^k.at n=23A057491
• Composite numbers whose exponents in their canonical factorization lie in the geometric progression 1, 3, 9, ...at n=29A102838
• Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 110-111-100 pattern in any orientation.at n=9A146187
• A sequence a(n) such that a(n+1)^2 - a(n)^2 are perfect squares.at n=8A180313
• Sum of number of unitary divisors (A034444) from 1 to 10^n.at n=4A180361
• Numbers k such that sopfr(k) = tau(k)^2.at n=36A305026
• a(n) is the (n-1)-st frugal number in base n.at n=36A379539
• a(n) is the index where A387090(n) appears in A386482.at n=49A386484