

A231533


Decimal expansion of the negative imaginary part of Sum_{n=0..inf}(1/c_n), c_0=1, c_n=c_(n1)*(n+I).


3



9, 2, 8, 5, 6, 0, 7, 7, 7, 3, 2, 1, 8, 4, 5, 5, 8, 6, 6, 6, 7, 2, 0, 2, 9, 3, 2, 8, 5, 6, 6, 9, 8, 7, 2, 0, 2, 8, 9, 8, 6, 9, 7, 4, 6, 3, 3, 1, 5, 6, 5, 6, 5, 9, 9, 9, 2, 3, 1, 4, 8, 3, 3, 9, 0, 9, 9, 5, 0, 0, 6, 1, 7, 0, 2, 6, 0, 3, 6, 5, 9, 7, 6, 7, 1, 9, 0, 7, 4, 5, 8, 4, 5, 5, 1, 2, 2, 7, 1, 8, 1, 0, 0, 7, 1
(list;
constant;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,1


COMMENTS

Consider an extension of exp(x) to an intriguing function, expim(x,y), defined by the power series Sum_{n=0..inf}(x^n/c_n), where c_0 = 1, c_n = c_(n1)*(n+y*I), so that exp(x) = expim(x,0). The current sequence regards the negative imaginary part of the complex expim(1,1). The decimal expansion of the real part is in A231532 and that of the absolute value in A231534.


LINKS

Stanislav Sykora, Table of n, a(n) for n = 0..10000


FORMULA

imag(Sum_{n=0..inf}(1/(A231530(n)+A231531(n)*I))).


EXAMPLE

0.92856077732184558666720293...


PROG

(PARI) Expim(x, y)={local (c, k, lastval, val); c = 1.0+0.0*I; lastval = c; k = 1; while (k, c*=x/(k + y*I); val = lastval + c; if (val==lastval, break); lastval = val; k += 1; ); return (val); }
imag(Expim(1, 1))


CROSSREFS

Cf. A231532, A231534, and A231530, A231531 (respectively the real and imaginary parts of the expansion coefficient's denominators).
Sequence in context: A252001 A098784 A105172 * A011453 A125580 A086238
Adjacent sequences: A231530 A231531 A231532 * A231534 A231535 A231536


KEYWORD

nonn,cons


AUTHOR

Stanislav Sykora, Nov 10 2013


STATUS

approved



