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A068345 Powers of 2, the fourth-from-last digit of which equals 7. 1
2097152, 16777216, 134217728, 4294967296, 1099511627776, 70368744177664, 72057594037927936, 4611686018427387904, 9444732965739290427392, 38685626227668133590597632, 19807040628566084398385987584 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

Sylvia Nasar, A Beautiful Mind (1998), p. 80.

LINKS

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

MATHEMATICA

Select[NestList[2#&, 1024, 150], Take[IntegerDigits[ # ], {-4, -4}][[1]]==7&]

CROSSREFS

Cf. A066867.

Sequence in context: A011571 A022537 A195236 * A194935 A016999 A017071

Adjacent sequences:  A068342 A068343 A068344 * A068346 A068347 A068348

KEYWORD

nonn,base

AUTHOR

Harvey P. Dale, Mar 06 2002

STATUS

approved

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Last modified December 9 17:18 EST 2019. Contains 329879 sequences. (Running on oeis4.)