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A321692
Digits of the 2-adic integer exp(-4).
2
1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0
OFFSET
0,1
COMMENTS
This is the multiplicative inverse of A320815.
FORMULA
a(n) = (A321689(n+1) - A321689(n))/2^n.
EXAMPLE
exp(-4) = ...00110000100100101000011101101111110000101.
PROG
(PARI) a(n) = lift(sum(i=0, n-(n>=2), Mod(4^i/i!, 2^(n+1))))\2^n
(PARI) a(n) = lift(exp(-4 + O(2^(n+1))))\2^n;
CROSSREFS
Sequence in context: A352678 A373371 A379651 * A355943 A102242 A005369
KEYWORD
nonn,base
AUTHOR
Jianing Song, Nov 17 2018
STATUS
approved