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A303744 Numbers that are not a difference between same powers (greater than 1) of positive numbers.

%I A303744 #24 Jun 25 2018 22:51:03
%S A303744 1,2,4,6,10,14,18,22,30,34,38,42,46,50,54,58,62,66,70,74,78,82,86,90,
%T A303744 94,102,106,110,114,118,122,126,130,134,138,142,146,150,154,158,162,
%U A303744 166,170,174,178,182,186,190,194,198,202,206,210,214,222,226,230,234,238,246,250,254,258,262,266,270,274,278,282,286,290
%N A303744 Numbers that are not a difference between same powers (greater than 1) of positive numbers.
%C A303744 Apart from 1 and 4, all terms == 2 (mod 4). - _Robert Israel_, Jun 25 2018
%H A303744 Robert Israel, <a href="/A303744/b303744.txt">Table of n, a(n) for n = 1..10000</a>
%e A303744 Odd numbers greater than 1 are differences of squares, so they are not here.
%e A303744 8 is not a term, 9 - 1: difference of two squares;
%e A303744 26 is not a term, 27 - 1: difference of two cubes.
%p A303744 N:= 1000: # to get all terms <= N
%p A303744 S:= {1,2,4,seq(i,i=6..N,4)}:
%p A303744 for p from 3 to ilog2(N+1) do
%p A303744   for n from 1 while n^p - (n-1)^p <= N do
%p A303744     if n^p > N then m0:= ceil((n^p - N)^(1/p)) else m0:= 1 fi;
%p A303744     for m from m0 to n-1 do
%p A303744       v:= n^p-m^p;
%p A303744       S:= S minus {v};
%p A303744     od
%p A303744 od od:
%p A303744 sort(convert(S,list)); # _Robert Israel_, Jun 25 2018
%Y A303744 Sequences of numbers that are difference of powers: A024352 (squares), A181123 (cubes).
%Y A303744 And of further n-th powers: A147857 (4th), A181124 (5th), A181125 (6th), A181126 (7th), A181127 (8th), A181128 (9th).
%K A303744 nonn
%O A303744 1,2
%A A303744 _Adam Kertesz_, Apr 29 2018