21927

Appears in sequences

• Number of 4's in all partitions of n.at n=37A024788
• Numerators of continued fraction convergents to sqrt(335).at n=4A041632
• Numbers whose base-5 representation contains exactly three 0's and three 2's.at n=21A045187
• Moebius transform of binomial(n+3, 4).at n=25A117109
• a(n) = least k such that the remainder when 28^k is divided by k is n.at n=24A128368
• Number of (n+1) X (n+1) -5..5 symmetric matrices with every 2 X 2 subblock having sum zero and one or three distinct values.at n=9A211331
• a(n) is the least number such that d(a(n)) = d(R(a(n)))/n, where R(n) is the digit reverse of n and d(n) is the number of divisors of n.at n=14A284495
• Expansion of Product_{k>=1} 1/(1 - x^(k*(k+1)/2))^A072964(k).at n=36A321507