A284669 Three-column array read by rows: the first row consists of the first two primes, p = 2 and q = 3, and their sum s = p + q = 5; afterwards the (n+1)-st row consists of the smallest pair of consecutive primes whose sum is a multiple of the sum in the n-th row followed by their sum.

2, 3, 5, 13, 17, 30, 29, 31, 60, 59, 61, 120, 113, 127, 240, 239, 241, 480, 953, 967, 1920, 3833, 3847, 7680, 15359, 15361, 30720, 30713, 30727, 61440, 368633, 368647, 737280, 737279, 737281, 1474560, 16220143, 16220177, 32440320, 32440319, 32440321, 64880640, 194641919

Offset

1,1

Comments

Values of k (ratio of consecutive sums): 6, 2, 2, 2, 2, 4, 4, 4, 2, 12, 2, 22, 2, 6, 5, 5, 20, 4, 12, 15, 22, 27, 8, 13, 20, 5, 12, 28, 22, 55, 3, 8, 29, 12, 18, 6, 39, 22, 11, 34, 3, 162, 24, 4, 25, 15, 7, 4, 6, 10.

Values of p (1st column): 2, 13, 29, 59, 113, 239, 953, 3833, 15359, 30713, 368633, 737279, 16220143, 32440319, 194641919, 973209577, 4866047987, 97320959993, 389283839993, 4671406079947, 70071091199959, 1541564006399999, 41622228172799993, 332977825382399987, 4328711729971199933, 86574234599423999983, 432871172997119999999, 5194454075965439999993, 145444714127032319999971, 3199783710794711039999977, 175988104093709107199999981

Links

Table of n, a(n) for n=1..43.

Example

In the 2nd row, 13 + 17 = 30 = 6*5, then 29 + 31 = 60 = 2*30, 59 + 61 = 120 = 2*60, etc.

Crossrefs

Sequence in context: A235638 A227829 A231481 * A154554 A105879 A066111

Adjacent sequences: A284666 A284667 A284668 * A284670 A284671 A284672

Keyword

nonn,tabf

Author

Zak Seidov, Apr 01 2017

Status

approved