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%I #15 Sep 19 2019 21:48:22
%S 1,4,0,1,2,9,8,4,6,4,3,2,4,8,1,7,0,7,0,9,2,3,7,2,9,5,8,3,2,8,9,9,1,6,
%T 1,3,1,2,8,0,2,6,1,9,4,1,8,7,6,5,1,5,7,7,1,7,5,7,0,6,8,2,8,3,8,8,9,7,
%U 9,1,0,8,2,6,8,5,8,6,0,6,0,1,4,8,6,6,3,8,1,8,8,3,6,2,1,2,1,5,8,2,0,3,1,2,5
%N Decimal expansion of 2^(-149).
%C Smallest positive representable value in IEEE-754 single-precision floating-point format when subnormal numbers (or denormalized numbers) are supported. See the Wikipedia link below for the single-precision representation of this number (thirty-one 0's and one 1).
%C This is the full sequence.
%C Some other facts about single-precision numbers: (i) there are 2^32 - 2^24 - 1 = 4278190079 representable numbers, because all 1's in the 8-bit exponent results in positive or negative infinity (depending on the sign bit), and 0 has two representations (all 0's or one 1 followed by thirty-one 0's); (ii) the largest representable number is 2^128 - 2^104 = 340282346638528859811704183484516925440 (sign bit = 0, exponent = 11111110, fraction = twenty-three 1's); (iii) the smallest non-representable positive integer is 2^24 + 1 = 16777217.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Single-precision_floating-point_format#Single-precision_examples">Single-precision floating-point format</a>
%e 2^(-149) = 1.40129846432481...*10^(-45).
%o (PARI) a(n) = if(n>=-44&&n<=60, digits(5^149)[n+45], 0)
%Y Cf. A321219 (for double-precision floating-point format).
%K nonn,cons,fini,full
%O -44,2
%A _Jianing Song_, Apr 27 2019
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