A343777
a(n) is the least integer that can be expressed as the sum of one or more consecutive nonzero n-gonal numbers in exactly n ways.
Original entry on oeis.org
2180, 554503705
Offset: 3
A368074
a(n) is the least number k such that the k-th n-gonal number can be written as the difference of two positive n-gonal numbers in exactly n ways.
Original entry on oeis.org
5, 12, 82, 105, 297, 182
Offset: 3
a(3) = 5: T(5) = T(6) - T(3) = T(8) - T(6) = T(15) - T(14), where T(k) is the k-th triangular number.
A368075
a(n) is the least n-gonal number that can be expressed as the difference of two positive n-gonal numbers in exactly n ways.
Original entry on oeis.org
15, 144, 10045, 21945, 220077, 99008
Offset: 3
a(3) = 15: 15 = 21 - 6 = 36 - 21 = 120 - 105.
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