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A154653
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Triangular T(n,k) = binomial(prime(n+1) - 1, prime(k+1) - 1) with T(n,0) = 1, read by rows.
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2
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1, 1, 1, 1, 6, 1, 1, 15, 15, 1, 1, 45, 210, 210, 1, 1, 66, 495, 924, 66, 1, 1, 120, 1820, 8008, 8008, 1820, 1, 1, 153, 3060, 18564, 43758, 18564, 153, 1, 1, 231, 7315, 74613, 646646, 646646, 74613, 7315, 1, 1, 378, 20475, 376740, 13123110, 30421755, 30421755, 13123110, 376740, 1
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OFFSET
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0,5
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COMMENTS
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Row sums are: {1, 2, 8, 32, 467, 1553, 19778, 84254, 1457381, 87864065, 354929117, ...}.
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LINKS
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FORMULA
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T(n,k) = binomial(prime(n+1) - 1, prime(k+1) - 1) with T(n,0) = 1.
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EXAMPLE
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Triangle begins as:
1;
1, 1;
1, 6, 1;
1, 15, 15, 1;
1, 45, 210, 210, 1;
1, 66, 495, 924, 66, 1;
1, 120, 1820, 8008, 8008, 1820, 1;
1, 153, 3060, 18564, 43758, 18564, 153, 1;
1, 231, 7315, 74613, 646646, 646646, 74613, 7315, 1;
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MAPLE
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seq(seq( `if`(k=0, 1, binomial(ithprime(n+1)-1, ithprime(k+1)-1) ), k=0..n), n=0..10); # G. C. Greubel, Dec 02 2019
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MATHEMATICA
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T[n_, k_]:= If[k==0, 1, Binomial[Prime[n+1] -1, Prime[k+1] -1]]; Table[T[n, k], {n, 0, 10}, {k, 0, n}]//Flatten
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PROG
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(PARI) T(n, k) = if(k==0, 1, binomial(prime(n+1)-1, prime(k+1)-1) ); \\ G. C. Greubel, Dec 02 2019
(Magma) [k eq 0 select 1 else Binomial(NthPrime(n+1)-1, NthPrime(k+1)-1): k in [0..n], n in [0..10]]; // G. C. Greubel, Dec 02 2019
(Sage)
def T(n, k):
if (k==0): return 1
else: return binomial(nth_prime(n+1)-1, nth_prime(k+1)-1)
[[T(n, k) for k in (0..n)] for n in (0..10)] # G. C. Greubel, Dec 02 2019
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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