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A286238 Triangle A286239 reversed.

%I A286238 #14 Jun 10 2025 14:15:18
%S A286238 1,2,1,4,0,3,7,0,2,3,11,0,0,0,10,16,0,0,4,5,3,22,0,0,0,0,0,21,29,0,0,
%T A286238 0,7,0,5,10,37,0,0,0,0,0,8,0,21,46,0,0,0,0,11,0,0,14,10,56,0,0,0,0,0,
%U A286238 0,0,0,0,55,67,0,0,0,0,0,16,0,12,8,5,10,79,0,0,0,0,0,0,0,0,0,0,0,78,92,0,0,0,0,0,0,22,0,0,0,0,27,21,106,0,0,0,0,0,0,0,0,0,17,0,19,0,36
%N A286238 Triangle A286239 reversed.
%C A286238 See A286239.
%H A286238 Antti Karttunen, <a href="/A286238/b286238.txt">Table of n, a(n) for n = 1..10585; the first 145 rows of triangle/antidiagonals of array</a>
%F A286238 T(n,k) = A286239(k,n).
%e A286238 The first fifteen rows of triangle:
%e A286238     1,
%e A286238     2, 1,
%e A286238     4, 0, 3,
%e A286238     7, 0, 2, 3,
%e A286238    11, 0, 0, 0, 10,
%e A286238    16, 0, 0, 4,  5, 3,
%e A286238    22, 0, 0, 0,  0,  0, 21,
%e A286238    29, 0, 0, 0,  7,  0,  5, 10,
%e A286238    37, 0, 0, 0,  0,  0,  8,  0, 21,
%e A286238    46, 0, 0, 0,  0, 11,  0,  0, 14, 10,
%e A286238    56, 0, 0, 0,  0,  0,  0,  0,  0,  0, 55,
%e A286238    67, 0, 0, 0,  0,  0, 16,  0, 12,  8,  5, 10,
%e A286238    79, 0, 0, 0,  0,  0,  0,  0,  0,  0,  0,  0, 78,
%e A286238    92, 0, 0, 0,  0,  0,  0, 22,  0,  0,  0,  0, 27, 21,
%e A286238   106, 0, 0, 0,  0,  0,  0,  0,  0,  0, 17,  0, 19,  0, 36
%o A286238 (Scheme) (define (A286238 n) (A286239tr (A002024 n) (A038722 n))) ;; For A286239tr see A286239.
%o A286238 (Python)
%o A286238 from sympy import totient
%o A286238 def T(n, m): return ((n + m)**2 - n - 3*m + 2)//2
%o A286238 def t(n, k): return 0 if n%k!=0 else T(totient(n//k), k)
%o A286238 for n in range(1, 21): print([t(n, k) for k in range(1, n + 1)][::-1]) # _Indranil Ghosh_, May 09 2017
%Y A286238 Transpose: A286239 (triangle reversed).
%K A286238 nonn,tabl
%O A286238 1,2
%A A286238 _Antti Karttunen_, May 06 2017