A076062 Group the positive integers so that the n-th group contains n numbers whose sum is a multiple of the n-th prime.

2, 1, 5, 3, 4, 8, 6, 7, 9, 13, 10, 11, 12, 14, 19, 15, 16, 17, 18, 20, 31, 21, 22, 23, 24, 25, 26, 29, 27, 28, 30, 32, 33, 34, 35, 47, 36, 37, 38, 39, 40, 41, 42, 43, 52, 44, 45, 46, 48, 49, 50, 51, 53, 54, 82, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 87, 65, 66, 67, 68, 69, 70

Offset

1,1

Comments

The first n-1 numbers of row n are selected by simply choosing the smallest n-1 numbers which have not yet been used. The remaining number is then chosen to be the smallest possible unused number such that the sum of the n numbers is a multiple of prime(n). - Sean A. Irvine, Mar 16 2025

Links

Sean A. Irvine, Table of n, a(n) for n = 1..1540 (rows 1..20 flattened)

Example

2;
1,5;
3,4,8;
6,7,9,13;
10,11,12,14,19;
15,16,17,18,20,31; ...

Crossrefs

Cf. A076058, A076059, A076060, A076061.

Sequence in context: A193692 A344028 A075303 * A295563 A132582 A262211

Adjacent sequences: A076059 A076060 A076061 * A076063 A076064 A076065

Keyword

nonn,tabl,changed

Author

Amarnath Murthy, Oct 05 2002

Extensions

Corrected and extended by Sascha Kurz, Jan 20 2003

Status

approved