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Not a binomial number: not of form a^k +- b^k for k >= 2.
3

%I #7 Jan 03 2019 13:29:26

%S 6,14,22,30,38,42,46,62,66,70,78,86,94,102,110,114,118,134,138,142,

%T 150,154,158,166,174,182,186,190,198,206,210,214,222,230,238,246,254,

%U 258,262,266,270,278,282,286,294,302,310,318,322,326,330,334,350,354,358

%N Not a binomial number: not of form a^k +- b^k for k >= 2.

%H Robert Israel, <a href="/A079299/b079299.txt">Table of n, a(n) for n = 1..3614</a>

%p N:= 1000: # to get all terms <= N

%p kmax:= floor(LambertW(2*ln(2)*N)/ln(2)):

%p S:= {};

%p for k from 2 to kmax do

%p bmax:= floor((N/k)^(1/(k-1)));

%p S:= S union select(`<=`,{seq(seq(b^k-a^k,a=0..b-1),b=1..bmax), seq(seq(b^k+a^k,a=0..b),b=1..floor(N^(1/k)))},N);

%p od:

%p sort(convert({$1..N} minus S,list)); # _Robert Israel_, Jan 03 2019

%Y Complement of A079298.

%K nonn

%O 1,1

%A _David W. Wilson_, Feb 09 2003