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A376403
a(0) = 0, and for n > 0, a(n) = a(n-1) + A276076(a(n-1)), where A276076 is the factorial base exp-function.
5
0, 1, 3, 9, 39, 1089, 520179, 1466909163669354042297
OFFSET
0,3
COMMENTS
a(8) has 212 digits, a(9) has 10654 digits.
By induction, it is easy to see that formula a(n) = A276075(A376399(n)) implies that from the second term onward, this sequence gives the partial sums of A376399. See more comments in that sequence.
FORMULA
a(n) = A276075(A376399(n)).
a(0) = 0; and for n > 0, a(n) = a(n-1) + A376399(n-1) = Sum_{i=0..n-1} A376399(i).
PROG
(PARI)
A276076(n) = { my(m=1, p=2, i=2); while(n, m *= (p^(n%i)); n = n\i; p = nextprime(1+p); i++); (m); };
A376403(n) = if(!n, 0, A376403(n-1)+A276076(A376403(n-1)));
CROSSREFS
Cf. also A143293 (when prepended with 0, an analogous sequence for A276086).
Sequence in context: A340913 A079096 A143293 * A376401 A101395 A365121
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 02 2024
STATUS
approved