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.

Showing 1-4 of 4 results.

A309902 Approximation of the 5-adic integer exp(5) up to 5^n.

Original entry on oeis.org

0, 1, 6, 81, 456, 2956, 6081, 37331, 349831, 1521706, 3474831, 3474831, 101131081, 833552956, 4495662331, 16702693581, 16702693581, 169290584206, 1695169490456, 16953958552956, 55100931209206, 436570657771706, 2343919290584206, 9496476663631081
Offset: 0

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Author

Jianing Song, Aug 21 2019

Keywords

Comments

In p-adic field, the exponential function exp(x) is defined as Sum_{k>=0} x^k/k!. When extended to a function over the metric completion of the p-adic field, exp(x) has radius of convergence p^(-1/(p-1)) (i.e., exp(x) converges for x such that |x|_p < p^(-1/(p-1)), where |x|_p is the p-adic metric). As a result, for odd primes p, exp(p) is well-defined in p-adic field, and exp(4) is well defined in 2-adic field.
a(n) is the multiplicative inverse of A309903(n) modulo 5^n.

Crossrefs

Cf. A309903.
The 5-adic expansion of exp(5) is given by A309888.
Approximations of exp(p) in p-adic field: A309900 (p=3), this sequence (p=5), A309904 (p=7).

Programs

  • PARI
    a(n) = lift(exp(5 + O(5^n)))

A309887 Coefficients of 4-adic expansion of exp(4).

Original entry on oeis.org

1, 3, 0, 1, 1, 0, 0, 1, 2, 3, 0, 2, 0, 2, 3, 0, 2, 0, 3, 1, 2, 2, 1, 0, 2, 2, 3, 0, 3, 2, 2, 3, 0, 2, 1, 0, 0, 0, 2, 3, 0, 2, 0, 0, 3, 3, 3, 1, 3, 0, 2, 2, 3, 3, 3, 1, 0, 3, 1, 2, 0, 0, 2, 3, 3, 1, 1, 0, 2, 1, 3, 2, 1, 1, 0, 1, 2, 3, 2, 3, 1, 1, 2, 2, 0, 3, 3, 0, 1, 1, 1, 2, 0, 1, 3, 0, 2, 2, 0, 3
Offset: 0

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Author

Seiichi Manyama, Aug 21 2019

Keywords

Crossrefs

k-adic expansion of exp(k): A317675 (k=3), this sequence (k=4), A309888 (k=5).
Cf. A092426.

Programs

  • Maple
    op([1,3],padic:-evalp(exp(4),4,100)); # Robert Israel, Aug 02 2020
  • PARI
    N=100; Vecrev(digits(lift(exp(4+O(2^(2*N)))), 4), N)

A309975 Digits of the 5-adic integer exp(-5).

Original entry on oeis.org

1, 4, 2, 1, 3, 0, 2, 4, 1, 4, 1, 0, 4, 0, 4, 2, 1, 1, 4, 4, 2, 2, 3, 2, 2, 4, 3, 4, 4, 2, 0, 0, 1, 0, 4, 3, 2, 1, 3, 2, 0, 4, 3, 2, 4, 4, 1, 4, 0, 0, 4, 3, 4, 3, 0, 4, 3, 4, 1, 2, 4, 1, 3, 3, 3, 4, 3, 2, 4, 4, 3, 2, 4, 4, 3, 2, 4, 3, 4, 2, 2, 2, 0, 2, 3, 1, 3, 2
Offset: 0

Views

Author

Jianing Song, Aug 26 2019

Keywords

Comments

Digits of the multiplicative inverse of A309888.

Crossrefs

Cf. A309903.
Digits of exp(-p) in p-adic field: A309866 (p=3), this sequence (p=5), A309988 (p=7).

Programs

  • PARI
    a(n) = lift(exp(-5+O(5^(n+1))))\5^n

A309987 Digits of the 7-adic integer exp(7).

Original entry on oeis.org

1, 1, 4, 2, 0, 3, 2, 4, 3, 4, 2, 4, 0, 1, 1, 3, 3, 4, 5, 1, 0, 0, 1, 4, 5, 3, 3, 6, 6, 4, 5, 6, 2, 4, 3, 6, 2, 4, 5, 1, 0, 3, 2, 3, 5, 5, 2, 1, 3, 4, 3, 2, 5, 2, 5, 4, 1, 5, 6, 2, 1, 4, 0, 5, 0, 1, 6, 2, 0, 6, 0, 4, 4, 2, 1, 5, 0, 4, 4, 5, 5, 4, 5, 1, 5, 1, 0, 5
Offset: 0

Views

Author

Jianing Song, Aug 26 2019

Keywords

Comments

Digits of the multiplicative inverse of A309988.

Crossrefs

Cf. A309904.
Digits of exp(p) in p-adic field: A317675 (p=3), A309888 (p=5), this sequence (p=7).

Programs

  • PARI
    a(n) = lift(exp(7+O(7^(n+1))))\7^n
Showing 1-4 of 4 results.