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A100755 Smallest prime factor of the concatenation of terms in the n-th row of Pascal's Triangle. 3
11, 11, 11, 11, 7, 43, 29, 18285670562881, 5647, 13, 11, 523, 180642383, 41, 17, 7, 71, 31, 4506133, 13, 170777, 29, 1921778735419, 11, 31, 197, 13, 524243, 1294063654237511187554750201560780429214510015005200300103459729051895935678639157755876077558760678639155189593534597290200300101001500542921451560780475020118755237513654406291 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

a(4) = 11 is the least prime factor of 14641 = 11^4.

a(5) = 7 as 15101051 = 7* 2157293.

MATHEMATICA

f[n_] := (Table[ #[[1]], {1}] & /@ FactorInteger[ FromDigits[ Flatten[ Table[ IntegerDigits[ Binomial[n, k]], {k, 0, n}]]], FactorComplete -> False])[[1, 1]]; Table[ f[n], {n, 29}] (from Robert G. Wilson v Dec 02 2004)

CROSSREFS

Cf. A100756.

Sequence in context: A087380 A152986 A087994 * A171902 A045538 A084066

Adjacent sequences:  A100752 A100753 A100754 * A100756 A100757 A100758

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 23 2004

EXTENSIONS

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Dec 02 2004

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Last modified February 17 13:28 EST 2012. Contains 206031 sequences.