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A173560 Numbers m such that (6*m)^5 is a sum of a twin prime pair. 0
16, 44, 84, 135, 161, 631, 849, 880, 1035, 1086, 1721, 1815, 2155, 2704, 2871, 2975, 3011, 3159, 3220, 3365, 3390, 3669, 3996, 4075, 4704, 4761, 5025, 5090, 5299, 5585, 5640, 5970, 6314, 6606, 7035, 7785, 8104, 8129, 8610, 9116, 9665, 9966, 10249 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The twin prime pairs are characterized in A173255.

No such m has least significant digit (LSD) e = 2 or 7 because a = (6 * e)^5/2 - 1, representing the smaller of the twin primes, would get LSD 5.

No such m has LSD e = 3 or 8, because a+2 = (6 * e)^5/2 + 1, representing the larger prime, would get LSD 5.

The primes in this sequence here are a(6) = 631 = prime(115), a(11) = 1721 = prime(268),

a(17) = 3011 = prime(432), a(49) = 10859 = prime(1320),...

LINKS

Table of n, a(n) for n=1..43.

EXAMPLE

p = (6 * 16)^5/2 - 1 = 4076863487 = A000040(193435931); p+2 = A000040(193435932), so a(1) = 16.

p = (6 * 44)^5/2 - 1 = 641194278911 = A000040(24524572848); p+2 = A000040(24524572849), so a(2) = 44.

p = (6 * 84)^5/2 - 1 = 16260080320511 = A000040(553382827197); p+2 = A000040(553382827198), so a(3) = 84.

CROSSREFS

Cf. A001359, A061308, A069496, A172271, A172494, A173255

Sequence in context: A235413 A238255 A210375 * A293858 A258547 A211573

Adjacent sequences: A173557 A173558 A173559 * A173561 A173562 A173563

KEYWORD

hard,nonn

AUTHOR

Ulrich Krug (leuchtfeuer37(AT)gmx.de), Feb 21 2010

STATUS

approved

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Last modified November 26 21:15 EST 2022. Contains 358362 sequences. (Running on oeis4.)