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A114565 Dropping first and last digit of n leaves its largest prime factor. 0
128, 150, 175, 250, 378, 432, 450, 672, 750, 875, 1024, 1197, 1537, 1593, 1675, 2112, 2176, 2596, 3179, 3192, 3478, 3792, 3977, 4050, 4199, 4232, 4895, 5412, 5612, 6171, 6794, 7738, 8294, 8533, 9072, 9196, 9796, 10614, 10731, 11371, 11398 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..41.

EXAMPLE

Dropping first and last digit of 4199 leaves 19, which is the largest prime factor of 4199=13*17*19.

MATHEMATICA

Select[Range[100, 50000], (First@Last@FactorInteger@# == FromDigits@Rest@Most@IntegerDigits@#) &]

CROSSREFS

Sequence in context: A097758 A257446 A130445 * A243812 A194766 A257211

Adjacent sequences:  A114562 A114563 A114564 * A114566 A114567 A114568

KEYWORD

base,easy,nonn

AUTHOR

Giovanni Resta, Feb 15 2006

STATUS

approved

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Last modified March 29 18:37 EDT 2020. Contains 333117 sequences. (Running on oeis4.)