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A207890
a(0)=1; for n>=1,- the minimal increasing sequence, such that, for n>=1, the row sums of Pascal-like triangle with left side {1,1,1,...} and right side {a(0), a(1), a(2),...} form an increasing sequence of primes.
2
1, 1, 2, 3, 4, 5, 8, 11, 14, 17, 20, 29, 44, 55, 66, 69, 72, 77, 86, 149, 152, 167, 172, 183, 198, 229, 230, 233, 254, 267, 276, 285, 316, 355, 370, 377, 402, 423, 458, 469, 478, 517, 570, 623, 704, 725, 730, 753, 762, 801, 818, 839, 858, 861, 938, 943, 982
OFFSET
0,3
EXAMPLE
Triangle begins
n/k.|..0.....1.....2.....3.....4.....5.....6.....7
==================================================
.0..|..1
.1..|..1.....1
.2..|..1.....2.....2
.3..|..1.....3.....4.....3
.4..|..1.....4.....7.....7.....4
.5..|..1.....5....11....14....11.....5
.6..|..1.....6....16....25....25....16.....8
.7..|..1.....7....22....41....50....41....24.....11
.8..|
The row sums for n >= 1 form sequence A055496.
MATHEMATICA
rows={{1}, {1, 1}}; Table[(x=Flatten[{1, 2 MovingAverage[rows[[n]], 2]}]; sx=Apply[Plus, x]; z=NextPrime[sx, NestWhile[#+1&, 1, NextPrime[sx, #]-sx<Last[rows[[n]]]&]]-sx; rows=Append[rows, Append[x, z]]), {n, 2, 100}]; A207890=Map[Last[#]&, rows]
CROSSREFS
Cf. A055496.
Sequence in context: A343608 A144679 A309679 * A008825 A261629 A244395
KEYWORD
nonn,tabl
AUTHOR
STATUS
approved