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A369651
The second arithmetic derivative of primorial numbers.
4
0, 0, 1, 1, 32, 1, 1, 37712, 381596, 9835475, 36880858, 5221912091, 149759057759, 186024798, 456607833524310, 655374897748042, 32188411533060, 3002590335363139484, 1, 1, 1489192548103758778136571, 905624730150525686386253700, 1, 110832638787270947169636975150, 331748330219014906068858, 349669183443106226663011852002384
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OFFSET
0,5
COMMENTS
See comments in A024451.
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..49
FORMULA
a(n) = A003415(A024451(n)) = A068346(A002110(n)).
PROG
(PARI)
A002110(n) = prod(i=1, n, prime(i));
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A369651(n) = A003415(A003415(A002110(n)));
CROSSREFS
Cf. A002110, A003415, A024451, A068346, A109628 (positions of 1's).
Cf. also A368702.
Sequence in context: A354946 A351000 A174923 * A351809 A176341 A134203
Adjacent sequences: A369648 A369649 A369650 * A369652 A369653 A369654
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 31 2024
STATUS
approved

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Last modified September 28 11:26 EDT 2024. Contains 376292 sequences.
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