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A328313 For all such terms k in A143293 (partial sums of primorials) for which A129251(k) = 0, the term A276085(k) is included here. 7
2, 4, 2312, 3217644767340672907899084554132 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Construction: apply A276085 to the terms in the intersection of A143293 and A048103.
The next terms are quite big and can be found in the b-file. Note the nonmonotonic order, a(8) < a(5), a(6) and a(7).
A276086(a(n)) is in A143293, A276086(A276086(a(n))) is one of the primorials, A002110, and A276086(A276086(A276086(a(n)))) is a prime.
A327969(a(n)) <= 5 for all n.
LINKS
PROG
(PARI)
A002110(n) = prod(i=1, n, prime(i));
A143293(n) = if(n==0, 1, my(P=1, s=1); forprime(p=2, prime(n), s+=P*=p); (s)); \\ From A143293.
A276085(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*A002110(primepi(f[k, 1])-1)); };
A276086(n) = { my(i=0, m=1, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m*=(prime(i)^((n%nextpr)/pr)); n-=(n%nextpr)); pr=nextpr); m; };
k=0; for(n=1, 12, t = A143293(n); u = A276085(t); if(A276086(u) == t, k++; print1(u, ", ")));
CROSSREFS
Sequence in context: A102064 A085638 A134718 * A048829 A070655 A006263
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 12 2019
STATUS
approved

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)