1,1

Table of n, a(n) for n=1..6.

E. T. Bell, Exponential numbers, Amer. Math. Monthly, 41 (1934), 411-419.

The Prime Database, Bell(2841), the next term which is too large to include here.

Eric Weisstein's World of Mathematics, Bell Number

Bell(2)=2 and Bell(3)=5 are primes, Bell(4)..Bell(6) are composite, Bell(7)=877 is prime.

Cf. A000110, A051130.

Sequence in context: A208212 A176117 A078748 * A306785 A119748 A101341

Adjacent sequences: A051128 A051129 A051130 * A051132 A051133 A051134

nonn

Ignacio Larrosa CaĆ±estro

approved