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A102330
Triangle read by rows: n-th row consists of the lexicographically earliest set of n distinct primes whose sum is A068873(n).
3
2, 2, 3, 3, 5, 11, 2, 3, 5, 7, 3, 5, 7, 11, 17, 2, 3, 5, 7, 11, 13, 3, 5, 7, 11, 13, 17, 23, 2, 3, 5, 7, 11, 13, 19, 23, 3, 5, 7, 11, 13, 17, 19, 23, 29, 2, 3, 5, 7, 11, 13, 17, 19, 23, 31, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 3, 5, 7, 11, 13, 17
OFFSET
1,1
LINKS
Jean-François Alcover, Table of n, a(n) for n = 1..1225
EXAMPLE
Triangle begins:
2
2,3
3,5,11
2,3,5,7
3,5,7,11,17
2,3,5,7,11,13
3,5,7,11,13,17,23
2,3,5,7,11,13,19,23
3,5,7,11,13,17,19,23,29
2,3,5,7,11,13,17,19,23,31
3,5,7,11,13,17,19,23,29,31,41
2,3,5,7,11,13,17,19,23,29,31,37
3,5,7,11,13,17,19,23,29,31,37,41,47
2,3,5,7,11,13,17,19,23,29,31,37,41,43
3,5,7,11,13,17,19,23,29,31,37,41,43,47,53
MATHEMATICA
(* Computation verified with A068873. *)
row[n_] := Module[{s, m}, s = Select[{#, Total[#]}& /@ Subsets[ Prime[ Range[n+4]], {n}], PrimeQ[#[[2]]]&]; m = MinimalBy[s, #[[2]]&, 1]; If[s != {}, Return[m[[1, 1]]]]];
Array[row, 49] // Flatten (* Jean-François Alcover, Apr 23 2020 *)
CROSSREFS
By definition, row sums are A068873.
Sequence in context: A096010 A241507 A243927 * A103598 A103403 A052473
KEYWORD
easy,nonn,tabl
AUTHOR
Giovanni Teofilatto, Jan 30 2005
EXTENSIONS
Edited, corrected and extended by Ray Chandler, Feb 02 2005
Edited by N. J. A. Sloane, May 07 2014
STATUS
approved