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.

A386892 Numbers k expressible as x^y + y^z + z^x, where x, y, and z are integers > 1.

Original entry on oeis.org

12, 21, 36, 44, 61, 81, 89, 104, 105, 166, 172, 181, 276, 288, 289, 324, 395, 401, 480, 597, 673, 768, 773, 777, 932, 972, 1065, 1128, 1230, 1250, 1376, 1905, 2033, 2089, 2173, 2244, 2545, 2557, 3182, 3388, 3493, 4148, 4244, 4368, 4393, 4652, 4774
Offset: 1

Views

Author

Ian Hahus, Aug 06 2025

Keywords

Examples

			a(7) = 89, which can be given by x=4, y=3, z=2.
		

Crossrefs

Cf. A123207 (subsequence of primes).
Cf. A076980.

Programs

  • PARI
    upto(lim) = { my(L=List()); for(x=2, logint(lim,2), for(y=2, min(x,logint(lim,x)), for(z=2, min(x,logint(lim,y)), my(t=x^y+y^z+z^x); if(t<=lim, listput(L,t)) ))); Set(L) } \\ Andrew Howroyd, Aug 06 2025

A382211 Prime of the form p^q + q^r + r^p, for primes p, q and r.

Original entry on oeis.org

61, 181, 2557, 98057, 338323, 8389141, 48829699, 536871757, 1162268353, 2147484613, 2199023257237, 27368747340087430811, 196525143636054676607, 4656612873077421210401, 239072435917782732706099, 1978419655679387077928203, 9671406556917033397656301
Offset: 1

Views

Author

Karst Koymans, Mar 18 2025

Keywords

Examples

			61=2^2+2^5+5^2, 181=2^2+2^7+7^2, 2557=3^3+3^7+7^3, 98057=5^5+5^7+7^5. The first prime constructed from three different primes is 338323=3^11+11^5+5^3.
		

Crossrefs

Subsequence of A123207.
Showing 1-2 of 2 results.