18674

Appears in sequences

• Shifts left 2 places under "EFK" (unordered, size, unlabeled) transform.at n=21A032307
• Numbers k such that 30*k+{1,7,13,17,19,23,29} are all prime.at n=2A100419
• G.f. A(x) satisfies: the sum of the coefficients of x^k, k=0..n, in A(x)^n equals Sum_{k=0..n} C(n,k)^3 = A000172(n) (Franel numbers), for n>=0.at n=9A232687
• Number of perfect matchings on n edges which represent RNA secondary folding structures characterized by the Lyngso and Pedersen (L&P) family and the Cao and Chen (C&C) family.at n=9A289834
• Numbers k such that there are exactly 7 primes between 30*k and 30*k+30.at n=9A385124