A368919 - OEIS

A368919

Number of terms of A368917 less than 10^n, where A368917 lists the numbers k for which there is no prime p such that p^p divides the arithmetic derivative of A276086(k), where A276086 is the primorial base exp-function.

8, 88, 863, 8634, 86407, 864150, 8641439, 86414292

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OFFSET

1,1

COMMENTS

Value a(n) / 10^n seems to converge to 1 - lim_{n->oo} (A368911(n) / 10^n).

LINKS

Table of n, a(n) for n=1..8.

PROG

(PARI)

A327860(n) = { my(s=0, m=1, p=2, e); while(n, e = (n%p); m *= (p^e); s += (e/p); n = n\p; p = nextprime(1+p)); (s*m); };

A359550(n) = { my(f = factor(n)); prod(k=1, #f~, (f[k, 2]<f[k, 1])); };

A368916(n) = ((n>0)&&A359550(A327860(n)));

tp=10; s=0; for(n=1, 10^10, s+=A368916(n); if(1+n==tp, print1(s, ", "), if(n==tp, tp *= 10)));

CROSSREFS

Cf. A003415, A327860, A368911, A368916, A368917, A368920.

Sequence in context: A271939 A043043 A003492 * A053376 A053377 A053378

Adjacent sequences: A368916 A368917 A368918 * A368920 A368921 A368922

KEYWORD

nonn,more

AUTHOR

Antti Karttunen, Jan 14 2024

STATUS

approved