A365493 a(n) is the smallest number which can be represented as the sum of n n-almost primes in exactly n ways, or -1 if no such number exists.

2, 18, 44, 112, 418

Offset

1,1

Links

Table of n, a(n) for n=1..5.

Eric Weisstein's World of Mathematics, Almost Prime.

Example

For n = 2: 18 = 2*2 + 2*7 = 3*3 + 3*3.

Crossrefs

Cf. A091538, A365494.

Sequence in context: A189333 A072278 A296266 * A280316 A131538 A009820

Adjacent sequences: A365490 A365491 A365492 * A365494 A365495 A365496

Keyword

nonn,more

Author

Ilya Gutkovskiy, Sep 07 2023

Status

approved