A358634 a(n) is the smallest number k such that n consecutive integers starting at k have the same number of n-gonal divisors.

55, 844, 16652, 844529772, 243636414, 36289272509

Offset

3,1

Links

Table of n, a(n) for n=3..8.

Eric Weisstein's World of Mathematics, Polygonal Number

Index entries for sequences related to divisors of numbers

Example

16652 has 2 pentagonal divisors {1, 92}, 16653 has 2 pentagonal divisors {1, 5551}, 16654 has 2 pentagonal divisors {1, 22}, 16655 has 2 pentagonal divisors {1, 5}, and 16656 has 2 pentagonal divisors {1, 12}. These are the first 5 consecutive numbers with the same number of pentagonal divisors, so a(5) = 16652.

Crossrefs

Cf. A006558, A338628, A358044.

Sequence in context: A027784 A297523 A221786 * A241634 A008402 A281073

Adjacent sequences: A358631 A358632 A358633 * A358635 A358636 A358637

Keyword

nonn,more,hard

Author

Ilya Gutkovskiy, Nov 24 2022

Extensions

a(6)-a(8) from Martin Ehrenstein, Dec 04 2022

Status

approved