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A051318
Euclid-Mullin sequence (A000945) with initial value a(1)=43 instead of a(1)=2.
1
43, 2, 3, 7, 13, 53, 5, 6221671, 38709183810571, 139, 2801, 11, 17, 5471, 52662739, 23003, 30693651606209, 37, 1741, 1313797957, 887, 71, 7127, 109, 23, 97, 159227, 643679794963466223081509857, 103, 1079990819, 9539, 3143065813, 29, 3847, 89, 19, 577, 223
OFFSET
1,1
LINKS
Tyler Busby, Table of n, a(n) for n = 1..51 (terms 1..43 from Robert Price)
EXAMPLE
Product of first 28 terms +1 is 210102491806660945690525037461258737117339882568590700172677987135969766432980375 44232424110733238484973548134278212304532631, which is divisible by 103. Hence a(29)=103.
MATHEMATICA
a[1]=43; a[n_] := First[ Flatten[ FactorInteger[ 1+Product[ a[ j ], {j, n-1} ] ] ] ]; Array[a, 15]
PROG
(PARI) spf(n)=factor(n)[1, 1]
first(m)={my(v=vector(m), i, t=43); v[1]=43; for(i=2, m, v[i]=spf(t+1); t*=v[i]; ); v; } /* Anders Hellström, Jul 19 2015 */
CROSSREFS
Agrees with A000945 from 5th term. Cf. A000946, A005265, A005266.
Sequence in context: A357001 A114786 A139424 * A036202 A212316 A292996
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(31)-a(38) from Robert Price, Jul 19 2015
STATUS
approved