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Table of n, a(n) for n=1..95.
78125=5^7 follows 78121, the difference is 4. a(n)=1 only for some powers of 2.
Cf. A025475, A000961, A001597, A001694, A007917, A007918, A013632, A013633, A049711.
Sequence in context: A208083 A181515 A183045 * A079528 A143422 A071438
Adjacent sequences: A060844 A060845 A060846 * A060848 A060849 A060850
Labos Elemer, May 03 2001