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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A111107 Lexicographically smallest increasing sequence of primes whose binomial transform consists only of primes.

Original entry on oeis.org

2, 3, 5, 11, 13, 29, 43, 53, 59, 71, 79, 83, 103, 113, 139, 173, 181, 227, 269, 277, 317, 383, 463, 509, 673, 701, 751, 863, 967, 977, 1187, 1201, 1493, 1531, 1609, 1637, 1801, 2153, 2221, 2239, 2371, 2377, 2543, 2557, 2683, 2687, 2791, 2837, 3067, 3229, 3257
Offset: 0

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Author

Daniel Joyce, Oct 14 2005

Keywords

Comments

In the standard binomial transform of the primes most of the terms are composite.

Examples

			The binomial transform of this sequence gives: 2, 5, 13, 37, 101, 271, 727, 1931, 5003, 12547, 30449, 71761, ... = A384676.
The prime 7 and various larger primes are missing from the new sequence because the transform would not consist of primes. For example,
  2,5,13,33
  3,8,20
  5,12
  7
and 33 is not prime, so we must eliminate 7.
		

Crossrefs

Formula

a(n) = Sum_{i=0..n} A384676(n-i)*binomial(n,i)*(-1)^i. - Alois P. Heinz, Jun 06 2025

Extensions

Offset set to 0 by Alois P. Heinz, Jun 06 2025

A384768 Inverse binomial transform of A384674.

Original entry on oeis.org

2, 3, 3, 3, 3, 5, 11, 13, 7, 5, 7, 5, 3, 17, 29, 11, 11, 17, 13, 7, 29, 3, 3, 23, 3, 17, 37, 5, 223, 5, 37, 59, 19, 23, 433, 13, 89, 7, 7, 43, 3, 61, 5, 3, 191, 61, 149, 43, 89, 71, 13, 43, 41, 79, 31, 61, 23, 73, 53, 11, 157, 197, 83, 163, 3, 47, 7, 109, 5
Offset: 0

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Author

Keywords

Comments

All terms are primes.

Crossrefs

Formula

a(n) = Sum_{i=0..n} (-1)^(n-i) * A384674(i) * binomial(n,i).
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