A122867 Consider the array of sequences defined to be "the least previously nonoccurring positive integer such that partial sum + k is prime" beginning with k=0. This sequence is that array read by successive antidiagonals.

2, 1, 1, 1, 3, 4, 2, 2, 2, 6, 1, 6, 6, 4, 10, 2, 2, 8, 8, 6, 8, 1, 4, 4, 4, 4, 12, 12, 4, 4, 6, 6, 14, 14, 8, 16, 3, 2, 2, 12, 12, 10, 10, 10, 14, 2, 2, 6, 6, 8, 8, 12, 12, 14, 24, 1, 6, 4, 10, 10, 10, 10, 20, 20, 18, 30, 2, 2, 12, 6, 8, 8, 14, 14, 18, 18, 22, 22, 1, 4, 4, 8, 8, 16, 16, 18, 18, 16

Offset

1,1

Links

Table of n, a(n) for n=1..88.

Example

The array of sequences begins
k= 0: 2, 1, 4, 6, 10, 8, 12, 16, 14, 24, 30, 22, 18, 26, 34, ...,.
k= 1: 1, 3, 2, 4, 6, 12, 8, 10, 14, 18, 22, 26, 24, 16, 30, ...,.
k= 2: 1, 2, 6, 8, 4, 14, 10, 12, 20, 18, 16, 24, 26, 28, 32, ...,.
k= 3: 2, 6, 8, 4, 14, 10, 12, 20, 18, 16, 24, 26, 28, 32, 34, ...,.
k= 4: 1, 2, 4, 6, 12, 8, 10, 14, 18, 22, 26, 24, 16, 30, 32, ...,.
k= 5: 2, 4, 6, 12, 8, 10, 14, 18, 22, 26, 24, 16, 30, 32, 28, ...,.

Mathematica

f[s_] := Append[s, k = 1; p = q + Plus @@ s; While[MemberQ[s, k] || !PrimeQ[p + k], k++ ]; k]; T[n_, k_] := Nest[q = k; f, {}, n][[ -1]]; Table[T[k, n - k], {n, 13}, {k, n}] // Flatten

Crossrefs

Cf. A054408, A121861, A121862, A122866.

Sequence in context: A349574 A378522 A168377 * A124775 A140075 A099555

Adjacent sequences: A122864 A122865 A122866 * A122868 A122869 A122870

Keyword

nonn,tabl

Author

Jonathan Vos Post and Robert G. Wilson v, Sep 15 2006

Status

approved