Search: id:A112884 Results 1-1 of 1 results found. %I A112884 %S A112884 2,3,7,14,30,61,125,252,508,1019,2043,4090,8186,16377,32761,65528, %T A112884 131064,262135,524279,1048566,2097142,4194293,8388597 %N A112884 Number of bits required to represent binomial(2^n, 2^(n-1)). %F A112884 Appears to be equal to 2^n - floor(n / 2) %e A112884 a(2) = 3 because binomial(2^2, 2^1) in binary = 110 %o A112884 PHP code: $LastFact = gmp_init('1'); for ($i = 2; $i !== 65536; $i *= 2) { $Fact = gmp_fact($i); $Result = gmp_div_q($Fact, gmp_pow($OldFact, 2)); $LastFact = $Fact; echo gmp_strval($Result, 2).'
'; } %Y A112884 a(n) represents the size of A037293 in binary - see also the central binomial coefficients: A001405. %Y A112884 Sequence in context: A034065 A034075 A019595 this_sequence A103421 A151530 A000642 %Y A112884 Adjacent sequences: A112881 A112882 A112883 this_sequence A112885 A112886 A112887 %K A112884 easy,nonn %O A112884 1,1 %A A112884 Matt Erbst (matt(AT)erbst.org), Oct 04 2005 Search completed in 0.001 seconds