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A162371
Lexicographically earliest permutation of the natural numbers such that, when seen as a triangle read by rows, for n>1 the sums of rows are prime numbers.
5
1, 2, 3, 4, 5, 8, 6, 7, 9, 15, 10, 11, 12, 13, 21, 14, 16, 17, 18, 19, 23, 20, 22, 24, 25, 26, 27, 29, 28, 30, 31, 32, 33, 34, 35, 40, 36, 37, 38, 39, 41, 42, 43, 44, 47, 45, 46, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 68, 66, 67, 69, 70, 71, 72
OFFSET
1,2
COMMENTS
A162373 = row sums: A162373(n)=SUM(a(k):A000124(n-1)<=k<=A000217(n));
A162372 = right edge: A162372(n)=a(A000217(n));
A162375 = inverse: A162375(a(n))=n and a(A162375(n))=n;
A162374 = fixed points: a(A162374(n)) = A162374(n).
EXAMPLE
row ____________ initial terms _____________ row sum
1 : ................. 1 .......................... 1
2 : ............... 2 .. 3 ....................... 5
3 : ............. 4 .. 5 .. 8 ................... 17
4 : ........... 6 .. 7 .. 9 . 15 ................ 37
5 : ........ 10 . 11 . 12 . 13 . 21 ............. 67
6 : ...... 14 . 16 . 17 . 18 . 19 . 23 ......... 107
7 : .... 20 . 22 . 24 . 25 . 26 . 27 . 29 ...... 173
8 : .. 28 . 30 . 31 . 32 . 33 . 34 . 35 . 40 ... 263.
CROSSREFS
Sequence in context: A266406 A275152 A370794 * A376147 A269856 A146941
KEYWORD
nonn,tabl
AUTHOR
Reinhard Zumkeller, Jul 02 2009
STATUS
approved