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
Examples
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.
Links
- Eric Weisstein's World of Mathematics, Polygonal Number
- Index entries for sequences related to divisors of numbers
Extensions
a(6)-a(8) from Martin Ehrenstein, Dec 04 2022