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A047980 a(n) is smallest difference d of an arithmetic progression dk+1 whose first prime occurs at the n-th position. 2
1, 3, 24, 7, 38, 17, 184, 71, 368, 19, 668, 59, 634, 167, 512, 757, 1028, 197, 1468, 159, 3382, 799, 4106, 227, 10012, 317, 7628, 415, 11282, 361, 38032, 521, 53630, 3289, 37274, 2633, 63334, 1637, 34108, 1861, 102296, 1691, 119074, 1997, 109474, 2053 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Definition involves two minimal conditions: (1) the first prime (as in A034693) and (2) dk+1 sequences were searched with minimal d. Present terms are the first ones in sequences analogous to A034780, A034782-A034784, A006093 (called there K(n,m)).

Index of the first occurrence of n in A034693. - Amarnath Murthy, May 08 2003

LINKS

Table of n, a(n) for n=1..46.

Index entries for sequences related to primes in arithmetic progressions

FORMULA

a(n) = min{k | A034693(k) = n}

CROSSREFS

Cf. A034693, A034694, A034780, A034782 - A034784, A006093, A047981, A047982.

Sequence in context: A204578 A120085 A062834 * A084702 A168061 A065430

Adjacent sequences:  A047977 A047978 A047979 * A047981 A047982 A047983

KEYWORD

nonn

AUTHOR

Labos Elemer

STATUS

approved

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Last modified December 17 19:18 EST 2014. Contains 252038 sequences.