A004210 -id:A004210 - cp's OEIS frontend

A206524 By definition, the sequences A004210, A206522 and A206523 are disjoint; the present sequence gives the complement of their union.

6, 14, 16, 36, 50, 53, 54, 56, 57, 63, 65, 74, 77, 78, 81, 84, 86, 88, 95, 96, 101, 102, 107, 109, 113, 115, 116, 127, 132, 134, 136, 137, 141, 142, 148, 150, 151, 154, 155, 163, 166, 168, 173, 177, 180, 181, 182, 185, 188, 192, 196, 197, 200, 207, 209, 213, 216, 218, 221, 222, 223, 224, 225, 226, 229, 231, 234, 237, 239, 240, 241, 243, 244, 247, 254

Offset: 1

N. J. A. Sloane, Feb 08 2012

nonn

Cf. A004210, A206522, A206524.

A206522 The pairwise differences of the terms of A004210.

Original entry on oeis.org

2, 5, 7, 10, 12, 13, 15, 17, 20, 22, 23, 24, 25, 27, 28, 29, 32, 34, 35, 37, 39, 40, 41, 42, 45, 47, 49, 52, 55, 58, 59, 60, 62, 64, 66, 69, 71, 72, 76, 79, 80, 82, 83, 87, 89, 92, 94, 99, 100, 103, 104, 105, 106, 111, 112, 114, 117, 118, 119, 121, 124, 126, 128, 129, 131, 135, 138, 139, 143, 144, 145, 146, 147, 149, 153, 156, 158, 159, 160, 167, 170, 171, 172, 174, 175

Offset: 1

N. J. A. Sloane, Feb 08 2012

nonn

Cf. A004210, A206523, A206524.

A206523 The pairwise sums of the terms of A004210.

Original entry on oeis.org

4, 9, 11, 19, 21, 26, 31, 33, 38, 44, 46, 48, 51, 61, 68, 70, 73, 75, 85, 91, 93, 97, 98, 108, 110, 120, 123, 125, 130, 133, 140, 152, 157, 162, 164, 165, 169, 179, 189, 191, 203, 204, 205, 210, 212, 220, 228, 232, 245, 251, 261, 263, 268, 269, 278, 283, 290, 292, 303, 306, 308, 313, 323, 324, 327, 335, 348, 350, 363, 372, 382, 389, 391, 395, 396, 406, 417, 418, 419, 421

Offset: 1

N. J. A. Sloane, Feb 08 2012

nonn

Cf. A004210, A206522, A206524.

A126428 a(1) = 1; for n > 1, a(n) = smallest number > a(n-1) such that pairwise sums and (absolute) differences of distinct elements are all distinct.

Original entry on oeis.org

1, 2, 6, 12, 21, 37, 58, 84, 112, 129, 173, 213, 266, 307, 373, 446, 513, 589, 639, 829, 916, 1061, 1209, 1297, 1429, 1461, 1626, 1783, 1964, 2220, 2576, 2653, 2875, 3064, 3307, 3605, 3889, 4228, 4332, 4412, 4658, 5337, 5618, 5647, 6281, 6511, 7001, 7388

Offset: 1

Philippe Lallouet (philip.lallouet(AT)wanadoo.fr), Mar 11 2007, Jul 27 2007

nonn

			a(1) = 1, a(2) = 2; n = 3: k = 3, k-a(2) = 1 = a(2)-a(1), so a(3) > 3; k = 4: k-a(1) = 3 = a(1)+a(2), so a(3) > 4; k = 5: k-a(2) = 3 = a(1)+a(2), so a(3) > 5; k=6: k-a(1) = 5, k-a(2) = 4, k+a(1) = 7, k+a(2) = 8, a(2)-a(1) = 1, a(2)+a(1) = 3 are all distinct, hence a(3) = 6.

Klaus Brockhaus, Table of n, a(n) for n = 1..2000
Eric Weisstein's World of Mathematics, B2-Sequence
Index entries for B_2 sequences

Cf. A005282 (Mian-Chowla sequence).

import Data.List (intersect)
a126428 n = a126428_list !! (n-1)
a126428_list =  magics 1 [] [] where
   magics :: Integer -> [Integer] -> [Integer] -> [Integer]
   magics n ms tests
      | tests `intersect` nMinus == [] && tests `intersect` nPlus == []
      = n : magics (n+1) (n:ms) (nMinus ++ nPlus ++ tests)
      | otherwise
      = magics (n+1) ms tests
      where nMinus = map (n -) ms
            nPlus  = map (n +) ms
-- magics is the generator for a004210_list, cf. A004210, magic integers.
-- Reinhard Zumkeller, Mar 03 2011

{m=48; u=[]; s=Set(); k=0; for(n=1, m, b=1; while(b, b=0; k++; j=0; while(!b&&j<#u, j++; if(setsearch(s, k-u[j])||setsearch(s, k+u[j]), b=1))); print1(k, ","); if(n

Edited and extended by Klaus Brockhaus, Sep 05 2007

cp's OEIS Frontend

A206524 By definition, the sequences A004210, A206522 and A206523 are disjoint; the present sequence gives the complement of their union.

Views

Author

Keywords

Crossrefs

A206522 The pairwise differences of the terms of A004210.

Views

Author

Keywords

Crossrefs

A206523 The pairwise sums of the terms of A004210.

Views

Author

Keywords

Crossrefs

A126428 a(1) = 1; for n > 1, a(n) = smallest number > a(n-1) such that pairwise sums and (absolute) differences of distinct elements are all distinct.

Views

Author

Keywords

Examples

Links

Crossrefs

Programs

Haskell

PARI

Extensions