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A350405
a(n) is the smallest number which can be represented as the sum of n distinct nonzero n-gonal numbers in exactly n ways, or 0 if no such number exists.
9
37, 142, 285, 536, 911, 1268, 1909, 2713, 3876, 5179, 6891, 8901, 11190, 14384, 18087, 21697, 27055, 32166, 39111, 46560, 53892, 64412, 73949, 86778, 98202, 113635, 130088, 148051, 167505, 190968, 214955, 240143, 269775, 297615, 331201, 367429, 409179, 451340, 497830
OFFSET
3,1
LINKS
Eric Weisstein's World of Mathematics, Polygonal Number
FORMULA
a(n) >= A006484(n). - David A. Corneth, Dec 30 2021
EXAMPLE
For n = 3: 37 = 1 + 15 + 21 = 3 + 6 + 28 = 6 + 10 + 21.
MATHEMATICA
Do[i=1; While[b=PolygonalNumber[n, Range@i++]; !IntegerQ[t=Min[First/@Select[Tally[Select[Total/@Subsets[b, {n}], #<=Max@b&]], Last@#==n&]]]]; Print@t, {n, 3, 10}] (* Giorgos Kalogeropoulos, Dec 30 2021 *)
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 29 2021
EXTENSIONS
a(10)-a(31) from Michael S. Branicky, Dec 29 2021
More terms from David A. Corneth, Dec 30 2021
STATUS
approved