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Triangle T(n,k) read by rows, where each row lists the value of n coins, in cents, using k dimes (10 cents) and n-k quarters (25 cents).
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%I #12 Nov 10 2022 16:12:27

%S 0,25,10,50,35,20,75,60,45,30,100,85,70,55,40,125,110,95,80,65,50,150,

%T 135,120,105,90,75,60,175,160,145,130,115,100,85,70,200,185,170,155,

%U 140,125,110,95,80,225,210,195,180,165,150,135,120,105,90,250,235,220,205,190

%N Triangle T(n,k) read by rows, where each row lists the value of n coins, in cents, using k dimes (10 cents) and n-k quarters (25 cents).

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Change-making_problem">Change-making problem</a>

%H <a href="/index/Mag#change">Index entries for sequences related to making change.</a>

%F T(n,k) = 10*k + 25*(n-k), 0 <= k <= n.

%e Triangle begins

%e n\k | 0 1 2 3 4 5 6 7 8 9 10

%e ----|----------------------------------------------------------

%e 0 | 0

%e 1 | 25 10

%e 2 | 50 35 20

%e 3 | 75 60 45 30

%e 4 | 100 85 70 55 40

%e 5 | 125 110 95 80 65 50

%e 6 | 150 135 120 105 90 75 60

%e 7 | 175 160 145 130 115 100 85 70

%e 8 | 200 185 170 155 140 125 110 95 80

%e 9 | 225 210 195 180 165 150 135 120 105 90

%e 10 | 250 235 220 205 190 175 160 145 130 115 100

%e ...

%t T[n_, k_] := T[n, k] = 10 k + 25 (n - k); Table[T[n, k], {n, 0, 10}, {k, 0, n}] // Flatten

%Y Cf. A008592 (right diagonal), A008607 (1st column).

%Y Cf. A351726.

%K nonn,easy,tabl

%O 0,2

%A _Wesley Ivan Hurt_, Oct 30 2022