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A376407
a(0) = 0, and for n > 0, a(n) = a(n-1) + A019565(a(n-1)), where A019565 is the base-2 exp-function.
3
0, 1, 3, 9, 23, 353, 10519, 12086209, 1174153011340170531, 73582975079922326904310062621361286634299329277087298285
OFFSET
0,3
COMMENTS
a(10) has 272 digits and a(11) has 1523 digits.
By induction, it is easy to see that formula a(n) = A048675(A376406(n)) implies that from the second term onward, this sequence gives the partial sums of A376406. See comments and examples in that sequence.
FORMULA
a(n) = A048675(A376406(n)).
a(0) = 0; and for n > 0, a(n) = a(n-1) + A376406(n-1) = Sum_{i=0..n-1} A376406(i).
PROG
(PARI)
A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };
A376407(n) = if(!n, 0, my(x=A376407(n-1)); x+A019565(x));
CROSSREFS
Cf. also A376403 (an analogous sequence for A276076).
Sequence in context: A146472 A145955 A129834 * A029488 A198681 A254010
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 04 2024
STATUS
approved