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 1-2 of 2 results.

A353406 Stirling transform of odd primes.

Original entry on oeis.org

3, 8, 25, 91, 376, 1715, 8471, 44838, 252903, 1514213, 9590874, 64056173, 449804453, 3312346950, 25521479277, 205300781275, 1720450321356, 14986361037495, 135393159641569, 1266006310597506, 12228936468908781, 121823473948915769, 1249794986354577736
Offset: 1

Views

Author

Ilya Gutkovskiy, May 07 2022

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n, m) option remember;
         `if`(n=0, ithprime(m+1), m*b(n-1, m)+b(n-1, m+1))
        end:
    a:= n-> b(n-1, 1):
    seq(a(n), n=1..23);  # Alois P. Heinz, May 13 2022
  • Mathematica
    nmax = 23; CoefficientList[Series[Sum[Prime[k + 1] (Exp[x] - 1)^k/k!, {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]! // Rest
    Table[Sum[StirlingS2[n, k] Prime[k + 1], {k, 1, n}], {n, 1, 23}]

Formula

E.g.f.: Sum_{k>=1} prime(k+1) * (exp(x) - 1)^k / k!.
a(n) = Sum_{k=1..n} Stirling2(n,k) * prime(k+1).

A354003 Inverse Stirling transform of A008578 (1 together with the primes).

Original entry on oeis.org

1, 1, -1, 3, -14, 84, -604, 5020, -47144, 492408, -5653004, 70681706, -955450018, 13878511166, -215521103888, 3562431678650, -62439880637498, 1156609714838858, -22575425757129216, 463085375385002432, -9959296414838153618, 224079866356625633070, -5264190202707104532482
Offset: 1

Views

Author

Ilya Gutkovskiy, May 13 2022

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 23; CoefficientList[Series[Log[1 + x] + Sum[Prime[k - 1] Log[1 + x]^k/k!, {k, 2, nmax}], {x, 0, nmax}], x] Range[0, nmax]! // Rest
    Table[Sum[StirlingS1[n, k] If[k == 1, 1, Prime[k - 1]], {k, 1, n}], {n, 1, 23}]

Formula

E.g.f.: log(1 + x) + Sum_{k>=2} prime(k-1) * log(1 + x)^k / k!.
a(n) = Sum_{k=1..n} Stirling1(n,k) * A008578(k).
Showing 1-2 of 2 results.