[seqfan] Natural angry numbers

Eric Angelini Eric.Angelini at kntv.be
Tue Oct 6 15:19:18 CEST 2009

Hello SeqFans,

another reordering of the Naturals (as I got no msg at all
for my former post -- sigh!);

Imagine that an angry natural number could not stand the
presence of his immediate neighbours -- thus asking them to
get away;

The acceptable "get away" distance would be given by the 
said angry Natural himself;

This means that "5", for instance, would not accept to see
"4" and "6" at a shorter distance than 5 integers from him;

Sequence S(1) is one packing of such Natural angry numbers:

S(1) = 1,4,7,2,10,13,16,3,5,.,.,8,.,.,.,6,11,.,.,.14,9,.,.,.,.,.,.,.,12,.,.,.,.,.,.,15

S(1) is build according to the "place the Naturals first" method
-- see former msg, here:

But we could also use the other building method -- "fill the
'holes' first":

S(2) = 1,3,5,7,9,2,11,13,4,15,17,6,19,21,8,23,25,27,10,29,31,12,...

S(2) comes lexicographically first,

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