A094150 Number of iterations of the sum of digits of the divisors of R(n) needed to reach 15, where R(n) = A002275.

5, 13, 12, 3, 11, 10, 15, 3, 14, 3, 5, 18, 13, 4, 18, 18, 5, 2, 4, 3, 12, 10, 21, 12, 18, 16, 11, 19, 20, 4, 6, 12, 13, 6, 6, 5, 3, 16, 5, 12, 12, 11, 18, 16, 18, 17, 12, 5, 12, 12, 18, 19, 14, 4, 5, 12, 18, 10, 16, 6, 13, 17, 21, 19, 6, 13, 19, 4, 3, 7, 15, 10, 21, 4, 18, 3, 5, 20, 11, 18

Offset

2,1

Links

Table of n, a(n) for n=2..81.

Example

a(9)=3 because 111111111 -> 151 -> 8 -> 15.
a(1) does not exist because 1 -> 1 and never reaches 15.

Crossrefs

Cf. A034690, A086793.

Sequence in context: A089534 A116981 A222756 * A375275 A130502 A320814

Adjacent sequences: A094147 A094148 A094149 * A094151 A094152 A094153

Keyword

less,nonn,base

Author

Jason Earls, Jun 01 2004

Extensions

More terms from David Wasserman, May 22 2007

Status

approved