38422

Appears in sequences

• a(1)=0; for n>1, a(n) = number of isomeric hydrocarbons of the acetylene series with carbon content n.at n=15A000642
• Numbers n such that n^9+9 and n^9-9 are prime.at n=32A239505
• Number of ways to write n as an ordered sum of 6 prime powers (including 1).at n=24A341135
• Cardinalities of the sets of fusible numbers obtained at the consecutive steps of their construction as follows. We set S(0) = {0}. S(n+1) is obtained by adding to S(n) the sums (x+y+1)/2 for all x,y from S(n) with the property |x-y| < 1. Then, a(n) is the number of elements in S(n).at n=13A343264