|
|
A062347
|
|
a(n) = (product of first n primes) modulo prime(n+1).
|
|
9
|
|
|
1, 2, 1, 2, 1, 9, 8, 18, 15, 17, 19, 11, 6, 26, 35, 27, 15, 55, 30, 24, 28, 4, 47, 56, 28, 28, 75, 25, 105, 30, 9, 52, 111, 89, 46, 132, 53, 97, 104, 106, 42, 94, 158, 184, 155, 5, 6, 45, 87, 78, 86, 26, 120, 33, 242, 66, 86, 2, 214, 2, 198, 127, 14, 112, 7, 141, 77, 309
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
|
|
EXAMPLE
|
a(4)=1 since 2*3*5*7 = 210 = 19*11 + 1.
|
|
MATHEMATICA
|
Mod[ #[ [ 1 ] ], #[ [ 2 ] ] ]&/@ Transpose[ {FoldList[ Times, 1, Prime[ Range[ 70 ] ] ], Prime[ Range[ 71 ] ]} ]
Join[{1}, Module[{nn=70, prs}, prs=Prime[Range[nn]]; Table[Mod[Fold[Times, Take[prs, n-1]], prs[[n]]], {n, 2, nn}]]] (* Harvey P. Dale, Jun 30 2024 *)
|
|
PROG
|
(PARI) { n=-1; f=1; forprime (p=2, prime(1001), write("b062347.txt", n++, " ", f%p); f*=p ) } \\ Harry J. Smith, Aug 05 2009
(Python) from sympy import sieve, primorial
print([1] + [primorial(k) % sieve[k+1] for k in range(1, 71)])
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|