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Odd elements in the 5-Pascal triangle A028313 that are not 1.
7

%I #17 Jan 12 2024 22:36:58

%S 5,7,7,19,19,9,27,27,9,65,65,11,101,101,11,57,147,231,231,147,57,13,

%T 69,69,13,273,273,15,355,855,855,355,15,111,451,2277,2277,451,111,17,

%U 127,1661,3487,5379,5379,3487,1661,127,17,689,2223,11583,11583,2223,689,19

%N Odd elements in the 5-Pascal triangle A028313 that are not 1.

%C Odd elements of A028314. - _G. C. Greubel_, Jan 06 2024

%H G. C. Greubel, <a href="/A028316/b028316.txt">Table of n, a(n) for n = 0..1000</a>

%e Odd elements of A028313 as an irregular triangle:

%e 5;

%e 7, 7;

%e 19, 19;

%e 9, 27, 27, 9;

%e 65, 65;

%e 11, 101, 101, 11;

%e 57, 147, 231, 231, 147, 57;

%e ...

%t A028314[n_, k_]:= Binomial[n+2,k+1] +3*Binomial[n,k];

%t f= Table[A028314[n,k], {n,0,100}, {k,0,n}]//Flatten;

%t a[n_]:= DeleteCases[{f[[n+1]]}, _?EvenQ];

%t Table[a[n], {n,0,150}]//Flatten (* _G. C. Greubel_, Jan 06 2024 *)

%o (Magma)

%o A028314:= func< n, k | Binomial(n+2, k+1) + 3*Binomial(n, k) >;

%o a:=[A028314(n, k): k in [0..n], n in [0..100]];

%o [a[n]: n in [1..150] | (a[n] mod 2) eq 1]; // _G. C. Greubel_, Jan 06 2024

%o (SageMath)

%o def A028314(n, k): return binomial(n+2, k+1) + 3*binomial(n, k)

%o a=flatten([[A028314(n, k) for k in range(n+1)] for n in range(101)])

%o [a[n] for n in (0..150) if a[n]%2==1] # _G. C. Greubel_, Jan 06 2024

%Y Cf. A028313, A028314, A028315, A028325.

%K nonn,tabf,easy

%O 0,1

%A _Mohammad K. Azarian_

%E More terms from _James A. Sellers_