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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A376682 Array read by antidiagonals downward where A(n,k) is the n-th term of the k-th differences of the noncomposite numbers (A008578).

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%I A376682 #17 Oct 18 2024 11:42:25
%S A376682 1,2,1,3,1,0,5,2,1,1,7,2,0,-1,-2,11,4,2,2,3,5,13,2,-2,-4,-6,-9,-14,17,
%T A376682 4,2,4,8,14,23,37,19,2,-2,-4,-8,-16,-30,-53,-90,23,4,2,4,8,16,32,62,
%U A376682 115,205,29,6,2,0,-4,-12,-28,-60,-122,-237,-442,31,2,-4,-6,-6,-2,10,38,98,220,457,899
%N A376682 Array read by antidiagonals downward where A(n,k) is the n-th term of the k-th differences of the noncomposite numbers (A008578).
%C A376682 Row k is the k-th differences of the noncomposite numbers.
%F A376682 A(i,j) = Sum_{k=0..j} (-1)^(j-k) binomial(j,k) A008578(i+k).
%e A376682 Array begins:
%e A376682          n=1:  n=2:  n=3:  n=4:  n=5:  n=6:  n=7:  n=8:  n=9:
%e A376682   -----------------------------------------------------------
%e A376682   k=0:    1     2     3     5     7    11    13    17    19
%e A376682   k=1:    1     1     2     2     4     2     4     2     4
%e A376682   k=2:    0     1     0     2    -2     2    -2     2     2
%e A376682   k=3:    1    -1     2    -4     4    -4     4     0    -6
%e A376682   k=4:   -2     3    -6     8    -8     8    -4    -6    14
%e A376682   k=5:    5    -9    14   -16    16   -12    -2    20   -28
%e A376682   k=6:  -14    23   -30    32   -28    10    22   -48    48
%e A376682   k=7:   37   -53    62   -60    38    12   -70    96   -70
%e A376682   k=8:  -90   115  -122    98   -26   -82   166  -166    86
%e A376682   k=9:  205  -237   220  -124   -56   248  -332   252   -86
%e A376682 Triangle begins:
%e A376682     1
%e A376682     2    1
%e A376682     3    1    0
%e A376682     5    2    1    1
%e A376682     7    2    0   -1   -2
%e A376682    11    4    2    2    3    5
%e A376682    13    2   -2   -4   -6   -9  -14
%e A376682    17    4    2    4    8   14   23   37
%e A376682    19    2   -2   -4   -8  -16  -30  -53  -90
%e A376682    23    4    2    4    8   16   32   62  115  205
%e A376682    29    6    2    0   -4  -12  -28  -60 -122 -237 -442
%e A376682    31    2   -4   -6   -6   -2   10   38   98  220  457  899
%t A376682 nn=12;
%t A376682 t=Table[Take[Differences[NestList[NestWhile[#+1&, #+1,!PrimeQ[#]&]&,1,2*nn],k],nn],{k,0,nn}]
%t A376682 (* or *)
%t A376682 nn=12;
%t A376682 q=Table[If[n==0,1,Prime[n]],{n,0,2nn}];
%t A376682 Table[Sum[(-1)^(j-k)*Binomial[j,k]*q[[i+k]],{k,0,j}],{j,0,nn},{i,nn}]
%Y A376682 The version for modern primes (A000040) is A095195.
%Y A376682 Initial rows: A008578, A075526, A036263 with 0 prepended.
%Y A376682 Column n = 1 is A030016 (modern A007442).
%Y A376682 A version for partitions is A175804, cf. A053445, A281425, A320590.
%Y A376682 Antidiagonal-sums are A376683 (modern A140119), absolute A376684 (modern A376681).
%Y A376682 First position of 0 is A376855 (modern A376678).
%Y A376682 For composite instead of prime we have A377033.
%Y A376682 For squarefree instead of prime we have A377038, nonsquarefree A377046.
%Y A376682 For prime-power instead of composite we have A377051.
%Y A376682 A000040 lists the primes, differences A001223, second A036263.
%Y A376682 Cf. A002808, A064113, A065890, A084758, A173390, A233671, A258025, A258026, A333254, A376602 (zeros), A376651 (positives), A376652 (negatives), A376680, A377037.
%K A376682 sign,tabl
%O A376682 0,2
%A A376682 _Gus Wiseman_, Oct 15 2024