1,2

Intersection of A037278 and A018252.

Table of n, a(n) for n=1..37.

a(n) = A037278(A176553(n)).

For n = 6; a(6) = 13721 because A176553(6) = 21, and divisors of 21 are 1, 3, 7, 21; concatenation of divisors A037278(21) = 13721 is noncomposite number.

Sequence in context: A210547 A202136 A123909 * A237423 A292003 A257373

Adjacent sequences: A176552 A176553 A176554 * A176556 A176557 A176558

nonn,base

Jaroslav Krizek, Apr 20 2010

Extended and edited by Charles R Greathouse IV, Apr 27 2010

approved