A344023 Numbers of the form p_1^1 + p_2^2 + ... + p_k^k where p_1 < p_2 < ... < p_k are distinct primes.
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
Keywords
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.
Links
- David A. Corneth, Table of n, a(n) for n = 1..10000
Programs
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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
Comments