21348

Appears in sequences

• Numbers k such that k+1 is composite and divides 3^k-2^k.at n=36A068410
• Small-number statistic from the enumeration of domino tilings of a 7-pillow of order n.at n=16A112841
• T(n,k)=Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any diagonal or antidiagonal neighbor, and containing the value n(n+1)/2-k-1.at n=48A211963
• Numbers n representable as x*y + x + y, where x >= y > 1, such that all x's and y's in all representation(s) of n are perfect squares.at n=29A258366
• Numbers that are the sum of eight fourth powers in nine or more ways.at n=21A345584
• Numbers that are the sum of eight fourth powers in ten or more ways.at n=10A345585