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A286248 Triangle A286249 reversed.

%I A286248 #19 Jun 10 2025 13:55:00
%S A286248 1,2,3,4,0,3,7,0,5,10,11,0,0,0,3,16,0,0,8,5,21,22,0,0,0,0,0,3,29,0,0,
%T A286248 0,12,0,14,36,37,0,0,0,0,0,8,0,10,46,0,0,0,0,17,0,0,5,21,56,0,0,0,0,0,
%U A286248 0,0,0,0,3,67,0,0,0,0,0,23,0,12,19,27,78,79,0,0,0,0,0,0,0,0,0,0,0,3,92,0,0,0,0,0,0,30,0,0,0,0,5,21,106,0,0,0,0,0,0,0,0,0,17,0,8,0,21
%N A286248 Triangle A286249 reversed.
%C A286248 See A286249.
%H A286248 Antti Karttunen, <a href="/A286248/b286248.txt">Table of n, a(n) for n = 1..10585; the first 145 rows of triangle/antidiagonals of array</a>
%F A286248 T(n,k) = A286249(k,n).
%e A286248 Triangle begins:
%e A286248    1,
%e A286248    2, 3,
%e A286248    4, 0, 3,
%e A286248    7, 0, 5, 10,
%e A286248   11, 0, 0,  0, 3,
%e A286248   ...
%o A286248 (Scheme) (define (A286248 n) (A286249tr (A002024 n) (A004736 n))) ;; For A286249tr, see A286249.
%o A286248 (Python)
%o A286248 from sympy import factorint
%o A286248 import math
%o A286248 def T(n, m): return ((n + m)**2 - n - 3*m + 2)//2
%o A286248 def P(n):
%o A286248     f = factorint(n)
%o A286248     return sorted([f[i] for i in f])
%o A286248 def a046523(n):
%o A286248     x=1
%o A286248     while True:
%o A286248         if P(n) == P(x): return x
%o A286248         else: x+=1
%o A286248 def t(n, k): return 0 if n%k!=0 else T(a046523(n//k), k)
%o A286248 for n in range(1, 21): print([t(n, k) for k in range(1, n + 1)][::-1]) # _Indranil Ghosh_, May 08 2017
%Y A286248 Transpose: A286249 (triangle reversed).
%K A286248 nonn,tabl
%O A286248 1,2
%A A286248 _Antti Karttunen_, May 06 2017