31826

Appears in sequences

• Smallest semiprime S starting a chain of exactly n semiprimes from iterating f(S) = 2*S+1.at n=7A114330
• Number of Ferrers diagrams with a single strictly smaller Ferrers puncture with the same orientation removed from the top with half-perimeter = n.at n=8A133107
• Number of 5 X n 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.at n=16A281473
• Smallest m such that A306305(m) = n.at n=18A306425
• Numbers k such that there is no prime p and index j > k such that A002182(j) = p * A002182(k).at n=12A309042
• Number of compositions (ordered partitions) of n into distinct parts, the least being 6.at n=60A339169
• a(n) = coefficient of x^n, n >= 0, in A(x) such that: 2 = Sum_{n=-oo..+oo} x^(2*n) * (1 - x^n)^(2*n) * A(x)^n.at n=13A357546