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.

A344023 Numbers of the form p_1^1 + p_2^2 + ... + p_k^k where p_1 < p_2 < ... < p_k are distinct primes.

Original entry on oeis.org

0, 2, 3, 5, 7, 11, 13, 17, 19, 23, 27, 28, 29, 31, 37, 41, 43, 47, 51, 52, 53, 54, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 123, 124, 126, 127, 128, 131, 136, 137, 139, 149, 151, 157, 163, 167, 171, 172, 173, 174, 176, 179, 180, 181, 191, 193, 197, 199
Offset: 1

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Author

Bernard Schott, May 07 2021

Keywords

Comments

Also, ordered distinct values taken by terms of A343300.
Primes form the subsequence corresponding to k = 1.

Examples

			0 is a term  because it is the empty sum.
11 is a term because 11 = 11^1 is prime and also 11 = 2^1 + 3^2.
52 is a term because 3^1 + 7^2 = 52.
1382 is a term because 2^1 + 7^2 + 11^3 = 13^1 +37^2 = 1382.
		

Crossrefs

Programs

  • PARI
    f(n) = my(fn=factor(n)); sum(k=1, #fn~, fn[k, 1]^k); \\ A343300
    lista(nn) = my(p=precprime(nn)); select(x->(x <=p), Set(vector(p, k, f(k)))); \\ Michel Marcus, May 08 2021