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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A351950 Arithmetic derivative of the factorial base exp-function: a(n) = A003415(A276076(n)).

Original entry on oeis.org

0, 1, 1, 5, 6, 21, 1, 7, 8, 31, 39, 123, 10, 45, 55, 185, 240, 705, 75, 275, 350, 1075, 1425, 3975, 1, 9, 10, 41, 51, 165, 12, 59, 71, 247, 318, 951, 95, 365, 460, 1445, 1905, 5385, 650, 2175, 2825, 8275, 11100, 30075, 14, 77, 91, 329, 420, 1281, 119, 483, 602, 1939, 2541, 7287, 840, 2905, 3745, 11165, 14910, 40845
Offset: 0

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Author

Antti Karttunen, Apr 01 2022

Keywords

Crossrefs

Differs from a similarly defined A327860 for the first time at n=24.
Coincides with A351951 on n given by A059590.

Programs

  • PARI
    A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
    A276076(n) = { my(i=0,m=1,f=1,nextf); while((n>0),i=i+1; nextf = (i+1)*f; if((n%nextf),m*=(prime(i)^((n%nextf)/f));n-=(n%nextf));f=nextf); m; };
    A351950(n) = A003415(A276076(n));

Formula

a(n) = A003415(A276076(n)).
a(n) = A327860(A351576(n)).