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A132403 Analogue of Pascal's triangle, but with "next prime" applied to each sum. 0
1, 2, 2, 3, 5, 3, 5, 11, 11, 5, 7, 17, 23, 17, 7, 11, 29, 41, 41, 29, 11, 13, 41, 71, 83, 71, 41, 13, 17, 59, 113, 157, 157, 113, 59, 17, 19, 79, 173, 271, 317, 271, 173, 79, 19, 23, 101, 257, 449, 593, 593, 449, 257, 101, 23, 29, 127, 359, 709, 1049, 1187, 1049, 709, 359 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Each number is the smallest prime => the sum of the 2 numbers above (consider each line padded with 0 on each side).

FORMULA

Array read by rows: A[k+1,n] = nextprime(A[k,n] + A[k,n+1]) = A007918(A[k,n] + A[k,n+1]).

EXAMPLE

Triangle begins:

1

2....2

3....5....3

5...11...11....5

7...17...23...17....7

11..29...41...41...29...11

13..41...71...83...71...41...13

17..59..113..157..157..113...59...17

19..79..173..271..317..271..173...79...19

23.101..257..449..593..593..449..257..101...23

29.127..359..709.1049.1187.1049..709..359..127..29

31.157..487.1069.1759.2237.2237.1759.1069..487.157..31

37.191..647.1559.2833.4001.4583.4001.2833.1559.647.191.37.

First column is primes A000040. Second column is A064337. Analogue of central binomial coefficient A000984 is the central numbers in this triangle, beginning: 1, 5, 23, 83, 317, 1187, 4583, 17327. Different triangles result if the first row is a pair other than (2,2). Asymmetric triangles occur if the first row consists of unequal integers.

The number under the middle of the row (2, 2) is 5 because 5 is smallest prime equal to or greater than 2+2 = 4.

CROSSREFS

Cf. A000040, A000984, A007918, A007308, A064337.

Sequence in context: A067330 A202874 A199512 * A113167 A036014 A076228

Adjacent sequences:  A132400 A132401 A132402 * A132404 A132405 A132406

KEYWORD

easy,nonn,tabl

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Nov 12 2007

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Last modified February 17 14:48 EST 2012. Contains 206048 sequences.