A153516 Triangle T(n,k,p,q,j) = T(n-1,k,p,q,j) + T(n-1,k-1,p,q,j) + (p*j+q)*prime(j)*T(n-2,k-1,p,q,j) with T(2,k,p,q,j) = prime(j) and (p,q,j) = (0,1,2), read by rows.

2, 3, 3, 2, 14, 2, 2, 25, 25, 2, 2, 33, 92, 33, 2, 2, 41, 200, 200, 41, 2, 2, 49, 340, 676, 340, 49, 2, 2, 57, 512, 1616, 1616, 512, 57, 2, 2, 65, 716, 3148, 5260, 3148, 716, 65, 2, 2, 73, 952, 5400, 13256, 13256, 5400, 952, 73, 2

Offset

1,1

Links

G. C. Greubel, Rows n = 1..50 of the triangle, flattened

Formula

T(n,k,p,q,j) = T(n-1,k,p,q,j) + T(n-1,k-1,p,q,j) + (p*j+q)*prime(j)*T(n-2,k-1,p, q,j) with T(2,k,p,q,j) = prime(j), T(3,2,p,q,j) = 2*prime(j)^2 - 4, T(4,2,p,q,j) = T(4,3,p,q,j) = prime(j)^2 - 2, T(n,1,p,q,j) = T(n,n,p,q,j) = 2 and (p,q,j) = (0,1,2).

Sum_{k=0..n} T(n,k,p,q,j) = 2*prime(j)^(n-1) for (p,q,j) = (0,1,2) = 2*A000244(n-1).

Example

Triangle begins as:
  2;
  3,  3;
  2, 14,   2;
  2, 25,  25,    2;
  2, 33,  92,   33,     2;
  2, 41, 200,  200,    41,     2;
  2, 49, 340,  676,   340,    49,    2;
  2, 57, 512, 1616,  1616,   512,   57,   2;
  2, 65, 716, 3148,  5260,  3148,  716,  65,  2;
  2, 73, 952, 5400, 13256, 13256, 5400, 952, 73, 2;

Mathematica

T[n_, k_, p_, q_, j_]:= T[n, k, p, q, j]= If[n==2, Prime[j], If[n==3 && k==2 || n==4 && 2<=k<=3, ((3-(-1)^n)/2)*Prime[j]^(n-1) -2^((3-(-1)^n)/2), If[k==1 || k==n, 2, T[n-1, k, p, q, j] + T[n-1, k-1, p, q, j] + (p*j+q)*Prime[j]*T[n-2, k-1, p, q, j] ]]];
Table[T[n, k, 0, 1, 2], {n, 12}, {k, n}]//Flatten (* modified by G. C. Greubel, Mar 03 2021 *)

Prog

(Sage)
@CachedFunction
def f(n, j): return ((3-(-1)^n)/2)*nth_prime(j)^(n-1) - 2^((3-(-1)^n)/2)
def T(n, k, p, q, j):
    if (n==2): return nth_prime(j)
    elif (n==3 and k==2 or n==4 and 2<=k<=3): return f(n, j)
    elif (k==1 or k==n): return 2
    else: return T(n-1, k, p, q, j) + T(n-1, k-1, p, q, j) + (p*j+q)*nth_prime(j)*T(n-2, k-1, p, q, j)
flatten([[T(n, k, 0, 1, 2) for k in (1..n)] for n in (1..12)]) # G. C. Greubel, Mar 03 2021
(Magma)
f:= func< n, j | Round(((3-(-1)^n)/2)*NthPrime(j)^(n-1) - 2^((3-(-1)^n)/2)) >;
function T(n, k, p, q, j)
  if n eq 2 then return NthPrime(j);
  elif (n eq 3 and k eq 2 or n eq 4 and k eq 2 or n eq 4 and k eq 3) then return f(n, j);
  elif (k eq 1 or k eq n) then return 2;
  else return T(n-1, k, p, q, j) + T(n-1, k-1, p, q, j) + (p*j+q)*NthPrime(j)*T(n-2, k-1, p, q, j);
  end if; return T;
end function;
[T(n, k, 0, 1, 2): k in [1..n], n in [1..12]]; // G. C. Greubel, Mar 03 2021

Crossrefs

Sequences with variable (p,q,j): this sequence (0,1,2), A153518 (0,1,3), A153520 (0,1,4), A153521 (0,1,5), A153648 (1,0,3), A153649 (1,1,4), A153650 (1,4,5), A153651 (1,5,6), A153652 (2,1,7), A153653 (2,1,8), A153654 (2,1,9), A153655 (2,1,10), A153656 (2,3,9), A153657 (2,7,10).

Cf. A000244.

Sequence in context: A184829 A338307 A153290 * A153311 A153312 A153283

Adjacent sequences: A153513 A153514 A153515 * A153517 A153518 A153519

Keyword

nonn,tabl,easy,less

Author

Roger L. Bagula, Dec 28 2008

Extensions

Edited by G. C. Greubel, Mar 03 2021

Status

approved