21326

Appears in sequences

• Replace n with concatenation of its divisors >1.at n=25A037277
• CONTINUANT transform of A002487: 1, 1, 2, 1, 3, 2, ...at n=10A071898
• Number of isolated-pentagon fullerenes with 2n vertices (or carbon atoms).at n=30A086423
• a(n) = Sum_{k=1..n} k*k', where n' is the arithmetic derivative of n.at n=43A190117
• Number of binary strings of length n that are "weak abelian squares".at n=15A230266
• Number of (n+1)X(1+1) 0..3 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=3A250529
• Number of (n+1) X (4+1) 0..3 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=0A250532
• T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=6A250536
• T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=9A250536
• Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum prime and every diagonal and antidiagonal sum nonprime.at n=5A251945
• Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum prime and every diagonal and antidiagonal sum nonprime.at n=2A251948
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum prime and every diagonal and antidiagonal sum nonprime.at n=30A251950
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum prime and every diagonal and antidiagonal sum nonprime.at n=33A251950
• Anagraprod Integers. Integers N that reproduce their multiset of digits when all the products of two successive digits of N are done (and considered together).at n=56A296451
• Number of partitions p of n such that (number of numbers in p that have multiplicity 1) != (number of numbers in p having multiplicity > 1).at n=38A330147
• a(n) = minimal positive k such that the concatenation of the decimal digits of n,n+1,...,n+k is divisible by n+k+1, or -1 if no such k exists.at n=51A332580
• G.f. satisfies A(x) = x + Sum_{n>=1} A(x^n)^2.at n=10A382315