cp's OEIS Frontend

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.

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A353572 Shifted variant of A342002: a(n) = A353571(A276086(n)), where A353571(x) = A003415(A003961(x)) / A003557(A003961(x)) and A276086 is the primorial base exp-function.

Original entry on oeis.org

0, 1, 1, 8, 2, 11, 1, 10, 12, 71, 19, 92, 2, 13, 17, 86, 24, 107, 3, 16, 22, 101, 29, 122, 4, 19, 27, 116, 34, 137, 1, 14, 16, 103, 27, 136, 18, 131, 167, 886, 244, 1117, 29, 164, 222, 1051, 299, 1282, 40, 197, 277, 1216, 354, 1447, 51, 230, 332, 1381, 409, 1612, 2, 17, 21, 118, 32, 151, 25, 152, 202, 991, 279
Offset: 0

Views

Author

Antti Karttunen, Apr 27 2022

Keywords

Crossrefs

Programs

  • PARI
    A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
    A003557(n) = (n/factorback(factorint(n)[, 1]));
    A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); }; \\ From A003961
    A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
    A353571(n) = { my(s=A003961(n)); (A003415(s)/A003557(s)); };
    A353572(n) = A353571(A276086(n));

Formula

a(n) = A353571(A276086(n)).
a(n) = A342002(A276154(n)).
For all n >= 0, a(n) >= A342002(n).

A353574 a(n) = A342002(n) / gcd(A342002(n), A342002(A276154(n))).

Original entry on oeis.org

1, 1, 5, 1, 7, 1, 7, 2, 31, 13, 41, 1, 9, 11, 37, 2, 47, 1, 11, 7, 43, 19, 53, 1, 13, 17, 49, 11, 59, 1, 9, 5, 41, 17, 55, 2, 59, 71, 247, 53, 317, 19, 73, 46, 289, 127, 359, 13, 87, 113, 331, 74, 401, 11, 101, 67, 373, 169, 443, 1, 11, 13, 47, 5, 61, 17, 69, 43, 277, 121, 347, 2, 83, 107, 319, 71, 389, 31, 97, 16
Offset: 1

Views

Author

Antti Karttunen, Apr 29 2022

Keywords

Comments

Compare the scatter plot to that of A342002.

Crossrefs

Programs

Formula

a(n) = A342002(n) / A353573(n) = A342002(n) / gcd(A342002(n), A353572(n)).
Showing 1-2 of 2 results.