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A090897 Next n digits of Pi. 7
3, 14, 159, 2653, 58979, 323846, 2643383, 27950288, 419716939, 9375105820, 97494459230, 781640628620, 8998628034825, 34211706798214, 808651328230664, 7093844609550582, 23172535940812848, 111745028410270193, 8521105559644622948, 95493038196442881097 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It seems that all terms have at least one prime factor that does not appear in the combined list of prime factors of the preceding terms of the sequence. - Mario Cortés, Aug 20 2020 [Checked up to n=65. - Michel Marcus, Aug 21 2020]

LINKS

Michel Marcus, Table of n, a(n) for n = 1..100

FORMULA

a(n) = floor( Pi * 10^(n*(n+1)/2-1) ) mod (10^n). - Carl R. White, Aug 13 2010

EXAMPLE

a(3) = 159 because after the first and the first two digits of Pi the next three are 159.

MAPLE

Partitioner := proc(cons, len) local i, R, spl; R := []; i:=0;

spl := L -> [seq([seq(L[i], i=1 + n*(n+1)/2..(n+1)*(n+2)/2)], n=0..len)]:

ListTools:-Reverse(convert(floor(cons*10^((len+1)*(len+2)/2)), base, 10)):

map(`@`(parse, cat, op), spl(%)) end:

aList := -> Partitioner(Pi, 20); aList(20); # Peter Luschny, Aug 22 2020

MATHEMATICA

With[{pi=RealDigits[Pi, 10, 500][[1]]}, FromDigits/@Table[Take[pi, {n (n-1)/2+1, (n(n+1))/2}], {n, 25}]] (* Harvey P. Dale, Dec 24 2011 *)

PROG

(PARI) lista(nn) = {my(nd = 5+nn*(nn+1)/2); default(realprecision, nd); my(vd = digits(floor(Pi*10^nd))); my(pos = 1); my(vr = vector(nn)); for (n=1, nn, vr[n] = fromdigits(vector(n, k, vd[k+ pos-1])); pos += n; ); vr; } \\ Michel Marcus, Aug 21 2020

CROSSREFS

Cf. A000796 (Pi), A016062, A081368.

Sequence in context: A330603 A261006 A185238 * A120459 A272368 A108798

Adjacent sequences:  A090894 A090895 A090896 * A090898 A090899 A090900

KEYWORD

easy,nonn,base

AUTHOR

Michael Joseph Halm, Feb 26 2004

STATUS

approved

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Last modified April 20 15:27 EDT 2021. Contains 343135 sequences. (Running on oeis4.)