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A097530
Least k such that k*P(n)#-P(n+6) and k*P(n)#+P(n+6) are both primes with P(i)=i-th prime and P(i)#=i-th primorial.
0
10, 4, 1, 1, 3, 3, 12, 1, 4, 15, 15, 14, 15, 27, 4, 24, 4, 5, 69, 182, 140, 25, 38, 32, 176, 344, 267, 6, 262, 181, 95, 272, 232, 765, 155, 281, 292, 3, 135, 259, 100, 38, 2, 411, 182, 778, 214, 132, 228, 258, 139, 45, 192, 633, 778, 118, 669, 214, 970, 583, 611, 524
OFFSET
1,1
MATHEMATICA
Primorial[n_] := Product[ Prime[i], {i, n}]; f[n_] := Block[{k = 1, p = Primorial[n], q = Prime[n + 6]}, While[k*p - q < 2 || !PrimeQ[k*p - q] || !PrimeQ[k*p + q], k++ ]; k]; Table[ f[n], {n, 62}] (* Robert G. Wilson v, Aug 31 2004 *)
CROSSREFS
Sequence in context: A038305 A089478 A028967 * A063565 A371918 A177390
KEYWORD
easy,nonn
AUTHOR
Pierre CAMI, Aug 27 2004
EXTENSIONS
More terms from Robert G. Wilson v, Aug 31 2004
STATUS
approved