A365507 - OEIS

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A365507

a(n) is the least positive integer that can be expressed as the sum of one or more consecutive n-almost primes in exactly n ways, or -1 if no such integer exists.

2, 10, 105, 2410, 45010, 708408

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..6.

Eric Weisstein's World of Mathematics, Almost Prime.

EXAMPLE

For n = 3: 105 = 3*5*7 = 2*2*3 + 2*3*3 + 2*2*5 + 3*3*3 + 2*2*7 = 2*2*5 + 3*3*3 + 2*2*7 + 2*3*5.

CROSSREFS

Cf. A054859, A091538, A186337.

Sequence in context: A087234 A273965 A273961 * A049538 A217901 A127728

Adjacent sequences: A365504 A365505 A365506 * A365508 A365509 A365510

KEYWORD

nonn,more

AUTHOR

Ilya Gutkovskiy, Sep 07 2023

STATUS

approved