156250000

Appears in sequences

• Smallest number that has exactly n substrings which are square.at n=17A035237
• Expansion of (1-x)^2/(1-5*x).at n=12A055842
• a(n) = det(M(n)) where M(n) is the n X n matrix defined by m(i,i)=6, m(i,j)=i/j.at n=10A079027
• 5th binomial transform of (1,1,0,0,0,0,.....).at n=11A081105
• a(n) = 5^n*(n^2 - n + 50)/50.at n=11A081911
• Hankel transform of central coefficients of (1+k*x+5x^2)^n, k arbitrary integer.at n=4A127947
• Sequence identical to its third differences in absolute values.at n=34A138278
• Squares that become cubes when their rightmost digit is removed.at n=9A226354
• Numbers n such that Sum_{i=1..j} 1/pn(i) + Sum_{i=1..k} 1/pd(i) is an integer, where pn are the prime factors of n and pd the prime factors of the arithmetic derivative of n, both counted with multiplicity.at n=20A239490
• Numbers n such that Sum_{i=1..j} 1/pn(i) - Sum_{i=1..k} 1/pd(i) is an integer, where pn are the prime factors of n and pd the prime factors of the arithmetic derivative of n, both counted with multiplicity.at n=14A239491
• Squares whose arithmetic derivative is a square.at n=8A266890
• Numbers n such that n = Sum_{i=1..j} (phi(n) mod d(i)), where phi(n) is the Euler totient function of n and d(i) are the divisors of n.at n=18A273292
• Numbers k such that k^4 is the sum of two positive 5th powers.at n=26A291852
• Numbers with 11 odd divisors.at n=16A368950
• Numbers k in A020487 with arithmetic derivative k' (A003415) in A020487.at n=22A377383