[go: up one dir, main page]

login
A078287
Least nontrivial multiple of the n-th prime beginning with 3.
9
30, 30, 30, 35, 33, 39, 34, 38, 322, 319, 310, 333, 328, 301, 329, 318, 354, 305, 335, 355, 365, 316, 332, 356, 388, 303, 309, 321, 327, 339, 381, 393, 3014, 3058, 3129, 302, 314, 326, 334, 346, 358, 362, 382, 386, 394, 398, 3165, 3122, 3178, 3206, 3029
OFFSET
1,1
LINKS
MAPLE
g := proc (n) local m, k;
for m from 0 do
k := max(2, ceil(3*10^m/n));
if k*n < 4*10^m then return k*n end if
end do
end proc:
seq(g(ithprime(i)), i=1..100); # Robert Israel, Feb 12 2018
MATHEMATICA
f[n_] := Block[{k = 2, m = n}, While[ IntegerDigits[k*m][[1]] != 3, k++ ]; k*m]; Table[ f[ Prime[n]], {n, 1, 55}]
PROG
(PARI) a(n) = {my(k=2, p=prime(n)); while(digits(k*p)[1] != 3, k++); k*p; } \\ Michel Marcus, Feb 12 2018
KEYWORD
base,easy,nonn,look
AUTHOR
Amarnath Murthy, Nov 26 2002
EXTENSIONS
Edited, corrected and extended by Robert G. Wilson v, Nov 29 2002
STATUS
approved