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A129250 Primes of Erdos-Selfridge class 16-. 2
22111003847, 25782283783, 34824831403, 42970472971, 44905511759, 45490491349, 52486961911, 54560052479, 55437374381, 65803884467, 66333011539 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Knowledge of a[k],k=1..9 allows us to establish A056637[17]=1+2*a[9]=110874748763.

LINKS

Table of n, a(n) for n=1..11.

FORMULA

{ a(n) } = { p=1+2*k*A129249[n] ; n=1,2,3..., k=1,2,3... such that p is prime and k has no factor of class > 15- }

PROG

(PARI) nextclass( a, s=-1, p, n=[] )={ if( !p, p=nextprime(a[ #a]+1)); print("Computing all primes of next class up to ", 2*p-s ); for( i=1, #a, for( k=1, p/a[i], if( is/*pseudo*/prime(2*k*a[i]-s), n=concat(n, 2*k*a[i]-s); ) ) ); vecsort(n) }; A129250=nextclass(A129249)

CROSSREFS

Cf. A056637, A081640, A081641, A129248, A129249.

Sequence in context: A119478 A101816 A186910 * A216398 A121841 A306503

Adjacent sequences:  A129247 A129248 A129249 * A129251 A129252 A129253

KEYWORD

more,nonn

AUTHOR

M. F. Hasler, Apr 21 2007

STATUS

approved

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Last modified December 13 01:23 EST 2019. Contains 329963 sequences. (Running on oeis4.)