A248713 a(1)=1; starting with n>1, concatenate distinct divisors which are in A050376 in increasing order and repeat until a term of A050376 is reached (a(n)=0 if no term of A050376 is ever reached).

1, 2, 3, 4, 5, 23, 7, 731173, 9, 25, 11, 31397, 13, 313, 1129, 16, 17, 29, 19, 59, 37, 211, 23, 731173, 25, 3251, 313, 47, 29, 547, 31, 313289, 311, 31397, 1129, 49, 37, 373, 313, 961, 41, 379, 43, 3137, 59, 223, 47, 479, 49, 71443, 317, 31123, 53, 239, 773

Offset

1,2

Comments

Fermi-Dirac analog of A037274 (terms of A050376 are Fermi-Dirac primes).

Links

Hiroaki Yamanouchi, Table of n, a(n) for n = 1..100

Example

We have 40 = 2*4*5 -> 245 = 5*49 -> 549 = 9*61 -> 961 is in A050376. So a(40) = 961.

Crossrefs

Cf. A037274, A050376, A084318.

Sequence in context: A037400 A080695 A239448 * A242799 A281588 A088865

Adjacent sequences: A248710 A248711 A248712 * A248714 A248715 A248716

Keyword

nonn,base

Author

Vladimir Shevelev, Oct 12 2014

Extensions

a(8) and a(34) corrected by Hiroaki Yamanouchi, Oct 13 2014

Status

approved