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A074179
a(1) = 1, a(n) = smallest multiple of n divisible by the sum of all previous terms.
1
1, 2, 3, 12, 90, 108, 1512, 1728, 3456, 34560, 456192, 497664, 12939264, 13934592, 139345920, 167215104, 5685313536, 6019743744, 228750262272, 240789749760, 481579499520, 10594748989440, 265831883735040, 277389791723520
OFFSET
1,2
LINKS
FORMULA
a(n) = lcm(n, Sum_{k=1..n-1} a(k)), with a(1) = 1. - Michel Marcus, Nov 11 2020
MAPLE
a[1] := 1:a[2] := 2:s := 3:for n from 3 to 50 do a[n] := lcm(s, n):s := s+a[n]:od:seq(a[k], k=1..50);
MATHEMATICA
nxt[{n_, a_, t_}]:={n+1, LCM[n+1, t], t+LCM[n+1, t]}; NestList[nxt, {1, 1, 1}, 30][[All, 2]] (* Harvey P. Dale, Dec 06 2018 *)
PROG
(PARI) lista(nn) = my(va=vector(nn)); va[1]=1; for (n=2, nn, va[n] = lcm(n, vecsum(va))); va; \\ Michel Marcus, Nov 11 2020
CROSSREFS
Cf. A057827.
Sequence in context: A012396 A013012 A009594 * A012586 A088223 A162053
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Aug 31 2002
EXTENSIONS
Corrected and extended by Sascha Kurz, Feb 12 2003
STATUS
approved