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A368907
a(n) = 1 if the k-th arithmetic derivative of A005940(1+n) is zero for some k >= 0, otherwise 0. Here A005940 is the Doudna sequence.
3
1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0
OFFSET
0
FORMULA
a(n) = A328308(A005940(1+n)).
PROG
(PARI)
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); (t); };
A003415checked(n) = if(n<=1, 0, my(f=factor(n), s=0); for(i=1, #f~, if(f[i, 2]>=f[i, 1], return(0), s += f[i, 2]/f[i, 1])); (n*s));
A328308(n) = if(!n, 1, while(n>1, n = A003415checked(n)); (n));
A368907(n) = A328308(A005940(1+n));
CROSSREFS
Cf. A003415, A005940, A328308, A368908 (partial sums).
Cf. also A328306, A368905.
Sequence in context: A304653 A132350 A076213 * A120525 A285373 A359543
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 11 2024
STATUS
approved