OFFSET

1,2

COMMENTS

Is it ever 0?

If all a(n)>0, then this is the inverse permutation of A064389. - M. F. Hasler, Nov 03 2014

After 10^12 terms of A064389, the first unknown term of this sequence is 5191516. - Benjamin Chaffin, Oct 09 2016

LINKS

Benjamin Chaffin, Table of n, a(n) for n = 1..20000 [First 6655 terms from Nick Hobson]

Nick Hobson, Python program for this sequence

PROG

(PARI) for(i=1, 9e9, for(j=1, #a064389, a064389[j]==i&&print1(j", ")+next(2)); break) \\ The terms of A064389 must be stored in the vector a064389. - M. F. Hasler, Nov 03 2014

CROSSREFS

KEYWORD

nonn

AUTHOR

Reiner Martin, Jan 08 2003

STATUS

approved