A374373 - OEIS

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A374373

Hexagonal numbers that are products of smaller hexagonal numbers.

1, 2850, 61776, 79800, 103740, 145530, 437580, 719400, 810901, 828828, 1050525, 1185030, 1788886, 2031120, 2162160, 2821500, 4250070, 4959675, 9217071, 12298320, 12457536, 16356340, 22899528, 23334696, 24890040, 30728880, 32800950, 45158256, 48565440, 58487520

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OFFSET

1,2

COMMENTS

There are infinitely many terms where the corresponding product has two factors. This can be proved by solving a certain generalized Pell equation, as in A374372.

LINKS

Table of n, a(n) for n=1..30.

EXAMPLE

1 is a term because it is a hexagonal number and equals the empty product.

2850 is a term because it is a hexagonal number and equals the product of the hexagonal numbers 15 and 190.

103740 is a term because it is a hexagonal number and equals the product of the hexagonal numbers 6, 91, and 190. (This is the first term that requires more than two factors.)

CROSSREFS

Row n=6 of A374370.

Cf. A000384, A374372.

Sequence in context: A234416 A218597 A259296 * A020429 A255026 A345588

Adjacent sequences: A374370 A374371 A374372 * A374374 A374375 A374376

KEYWORD

nonn

AUTHOR

Pontus von Brömssen, Jul 07 2024

STATUS

approved